diff --git a/content/base/public/nsIScriptLoaderObserver.idl b/content/base/public/nsIScriptLoaderObserver.idl
index f07cde36502e..7c2874c055c9 100644
--- a/content/base/public/nsIScriptLoaderObserver.idl
+++ b/content/base/public/nsIScriptLoaderObserver.idl
@@ -41,7 +41,7 @@
 interface nsIScriptElement;
 interface nsIURI;
 
-[scriptable, uuid(501209d3-7edf-437d-9948-3c6d1c08ef7f)]
+[scriptable, uuid(7b787204-76fb-4764-96f1-fb7a666db4f4)]
 interface nsIScriptLoaderObserver : nsISupports {
   
   /**
@@ -54,10 +54,6 @@ interface nsIScriptLoaderObserver : nsISupports {
    *        will not occur.
    * @param aElement The element being processed.
    * @param aIsInline Is this an inline script or externally loaded?
-   * @param aWasPending Did script processing have to be delayed,
-   *                    either for loading of an external script or
-   *                    because processing of an earlier scheduled
-   *                    script was delayed?
    * @param aURI What is the URI of the script (the document URI if
    *        it is inline).
    * @param aLineNo At what line does the script appear (generally 1
@@ -66,7 +62,6 @@ interface nsIScriptLoaderObserver : nsISupports {
   void scriptAvailable(in nsresult aResult, 
                        in nsIScriptElement aElement,
                        in boolean aIsInline,
-                       in boolean aWasPending,
                        in nsIURI aURI,
                        in PRInt32 aLineNo);
 
@@ -77,14 +72,9 @@ interface nsIScriptLoaderObserver : nsISupports {
    *        the script evaluation.
    * @param aElement The element being processed.
    * @param aIsInline Is this an inline script or externally loaded?
-   * @param aWasPending Did script processing have to be delayed,
-   *                    either for loading of an external script or
-   *                    because processing of an earlier scheduled
-   *                    script was delayed?
    */
   void scriptEvaluated(in nsresult aResult, 
                        in nsIScriptElement aElement,
-                       in boolean aIsInline,
-                       in boolean aWasPending);
+                       in boolean aIsInline);
 		       
 };
diff --git a/content/base/src/nsContentSink.cpp b/content/base/src/nsContentSink.cpp
index f6839b9ee983..f9bcb2da1c77 100644
--- a/content/base/src/nsContentSink.cpp
+++ b/content/base/src/nsContentSink.cpp
@@ -85,6 +85,7 @@
 #include "nsIRequest.h"
 #include "nsNodeUtils.h"
 #include "nsIDOMNode.h"
+#include "nsThreadUtils.h"
 
 PRLogModuleInfo* gContentSinkLogModuleInfo;
 
@@ -117,15 +118,14 @@ NS_IMETHODIMP
 nsScriptLoaderObserverProxy::ScriptAvailable(nsresult aResult,
                                              nsIScriptElement *aElement,
                                              PRBool aIsInline,
-                                             PRBool aWasPending,
                                              nsIURI *aURI,
                                              PRInt32 aLineNo)
 {
   nsCOMPtr<nsIScriptLoaderObserver> inner = do_QueryReferent(mInner);
 
   if (inner) {
-    return inner->ScriptAvailable(aResult, aElement, aIsInline, aWasPending,
-                                  aURI, aLineNo);
+    return inner->ScriptAvailable(aResult, aElement, aIsInline, aURI,
+                                  aLineNo);
   }
 
   return NS_OK;
@@ -134,13 +134,12 @@ nsScriptLoaderObserverProxy::ScriptAvailable(nsresult aResult,
 NS_IMETHODIMP
 nsScriptLoaderObserverProxy::ScriptEvaluated(nsresult aResult,
                                              nsIScriptElement *aElement,
-                                             PRBool aIsInline,
-                                             PRBool aWasPending)
+                                             PRBool aIsInline)
 {
   nsCOMPtr<nsIScriptLoaderObserver> inner = do_QueryReferent(mInner);
 
   if (inner) {
-    return inner->ScriptEvaluated(aResult, aElement, aIsInline, aWasPending);
+    return inner->ScriptEvaluated(aResult, aElement, aIsInline);
   }
 
   return NS_OK;
@@ -273,7 +272,6 @@ NS_IMETHODIMP
 nsContentSink::ScriptAvailable(nsresult aResult,
                                nsIScriptElement *aElement,
                                PRBool aIsInline,
-                               PRBool aWasPending,
                                nsIURI *aURI,
                                PRInt32 aLineNo)
 {
@@ -308,7 +306,7 @@ nsContentSink::ScriptAvailable(nsresult aResult,
   } else {
     mScriptElements.RemoveObjectAt(count - 1);
 
-    if (mParser && aWasPending && aResult != NS_BINDING_ABORTED) {
+    if (mParser && aResult != NS_BINDING_ABORTED) {
       // Loading external script failed!. So, resume parsing since the parser
       // got blocked when loading external script. See
       // http://bugzilla.mozilla.org/show_bug.cgi?id=94903.
@@ -317,7 +315,7 @@ nsContentSink::ScriptAvailable(nsresult aResult,
       //     script load, assuming that that error code means that the user
       //     stopped the load through some action (like clicking a link). See
       //     http://bugzilla.mozilla.org/show_bug.cgi?id=243392.
-      mParser->ContinueInterruptedParsing();
+      ContinueInterruptedParsingAsync();
     }
   }
 
@@ -327,8 +325,7 @@ nsContentSink::ScriptAvailable(nsresult aResult,
 NS_IMETHODIMP
 nsContentSink::ScriptEvaluated(nsresult aResult,
                                nsIScriptElement *aElement,
-                               PRBool aIsInline,
-                               PRBool aWasPending)
+                               PRBool aIsInline)
 {
   // Check if this is the element we were waiting for
   PRInt32 count = mScriptElements.Count();
@@ -347,8 +344,8 @@ nsContentSink::ScriptEvaluated(nsresult aResult,
     PostEvaluateScript(aElement);
   }
 
-  if (mParser && mParser->IsParserEnabled() && aWasPending) {
-    mParser->ContinueInterruptedParsing();
+  if (mParser && mParser->IsParserEnabled()) {
+    ContinueInterruptedParsingAsync();
   }
 
   return NS_OK;
@@ -1350,3 +1347,20 @@ nsContentSink::WillBuildModelImpl()
 
   mScrolledToRefAlready = PR_FALSE;
 }
+
+void
+nsContentSink::ContinueInterruptedParsing()
+{
+  if (mParser) {
+    mParser->ContinueInterruptedParsing();
+  }
+}
+
+void
+nsContentSink::ContinueInterruptedParsingAsync()
+{
+  nsCOMPtr<nsIRunnable> ev = new nsRunnableMethod<nsContentSink>(this,
+    &nsContentSink::ContinueInterruptedParsing);
+
+  NS_DispatchToCurrentThread(ev);
+}
diff --git a/content/base/src/nsContentSink.h b/content/base/src/nsContentSink.h
index c5e8460a1610..b5cdbe76d0b3 100644
--- a/content/base/src/nsContentSink.h
+++ b/content/base/src/nsContentSink.h
@@ -209,6 +209,9 @@ private:
 
 protected:
 
+  void ContinueInterruptedParsingAsync();
+  void ContinueInterruptedParsing();
+
   nsCOMPtr<nsIDocument>         mDocument;
   nsCOMPtr<nsIParser>           mParser;
   nsCOMPtr<nsIURI>              mDocumentURI;
diff --git a/content/base/src/nsScriptElement.cpp b/content/base/src/nsScriptElement.cpp
index e5e04991a345..bb1feb85ddd9 100755
--- a/content/base/src/nsScriptElement.cpp
+++ b/content/base/src/nsScriptElement.cpp
@@ -66,7 +66,6 @@ NS_IMETHODIMP
 nsScriptElement::ScriptAvailable(nsresult aResult,
                                  nsIScriptElement *aElement,
                                  PRBool aIsInline,
-                                 PRBool aWasPending,
                                  nsIURI *aURI,
                                  PRInt32 aLineNo)
 {
@@ -99,8 +98,7 @@ nsScriptElement::ScriptAvailable(nsresult aResult,
 NS_IMETHODIMP
 nsScriptElement::ScriptEvaluated(nsresult aResult,
                                  nsIScriptElement *aElement,
-                                 PRBool aIsInline,
-                                 PRBool aWasPending)
+                                 PRBool aIsInline)
 {
   nsresult rv = NS_OK;
   if (!aIsInline) {
diff --git a/content/base/src/nsScriptLoader.cpp b/content/base/src/nsScriptLoader.cpp
index 8f25a2241d8b..45d8129eb7ae 100644
--- a/content/base/src/nsScriptLoader.cpp
+++ b/content/base/src/nsScriptLoader.cpp
@@ -121,7 +121,7 @@ public:
   nsScriptLoadRequest(nsIScriptElement* aElement,
                       PRUint32 aVersion)
     : mElement(aElement),
-      mLoading(PR_TRUE), mWasPending(PR_FALSE),
+      mLoading(PR_TRUE),
       mIsInline(PR_TRUE),
       mJSVersion(aVersion), mLineNo(1)
   {
@@ -131,17 +131,15 @@ public:
 
   void FireScriptAvailable(nsresult aResult)
   {
-    mElement->ScriptAvailable(aResult, mElement, mIsInline, mWasPending,
-                              mURI, mLineNo);
+    mElement->ScriptAvailable(aResult, mElement, mIsInline, mURI, mLineNo);
   }
   void FireScriptEvaluated(nsresult aResult)
   {
-    mElement->ScriptEvaluated(aResult, mElement, mIsInline, mWasPending);
+    mElement->ScriptEvaluated(aResult, mElement, mIsInline);
   }
 
   nsCOMPtr<nsIScriptElement> mElement;
   PRPackedBool mLoading;             // Are we still waiting for a load to complete?
-  PRPackedBool mWasPending;          // Processed immediately or pending
   PRPackedBool mIsInline;            // Is the script inline or loaded?
   nsString mScriptText;              // Holds script for loaded scripts
   PRUint32 mJSVersion;
@@ -161,7 +159,8 @@ NS_IMPL_THREADSAFE_ISUPPORTS0(nsScriptLoadRequest)
 nsScriptLoader::nsScriptLoader(nsIDocument *aDocument)
   : mDocument(aDocument),
     mBlockerCount(0),
-    mEnabled(PR_TRUE)
+    mEnabled(PR_TRUE),
+    mHadPendingScripts(PR_FALSE)
 {
 }
 
@@ -226,7 +225,6 @@ IsScriptEventHandler(nsIScriptElement *aScriptElement)
   return PR_FALSE;
 }
 
-/* void processScriptElement (in nsIScriptElement aElement, in nsIScriptLoaderObserver aObserver); */
 nsresult
 nsScriptLoader::ProcessScriptElement(nsIScriptElement *aElement)
 {
@@ -445,7 +443,6 @@ nsScriptLoader::ProcessScriptElement(nsIScriptElement *aElement)
 
       request->mURI = scriptURI;
       request->mIsInline = PR_FALSE;
-      request->mWasPending = PR_TRUE;
       request->mLoading = PR_TRUE;
 
       nsCOMPtr<nsILoadGroup> loadGroup = mDocument->GetDocumentLoadGroup();
@@ -487,11 +484,8 @@ nsScriptLoader::ProcessScriptElement(nsIScriptElement *aElement)
     // If we've got existing pending requests, add ourselves
     // to this list.
     if (ReadyToExecuteScripts() && mPendingRequests.Count() == 0) {
-      NS_ASSERTION(!request->mWasPending, "should not be pending");
       return ProcessRequest(request);
     }
-
-    request->mWasPending = PR_TRUE;
   }
 
   // Add the request to our pending requests list
@@ -538,8 +532,8 @@ nsScriptLoader::FireScriptAvailable(nsresult aResult,
   for (PRInt32 i = 0; i < mObservers.Count(); i++) {
     nsCOMPtr<nsIScriptLoaderObserver> obs = mObservers[i];
     obs->ScriptAvailable(aResult, aRequest->mElement,
-                         aRequest->mIsInline, aRequest->mWasPending,
-                         aRequest->mURI, aRequest->mLineNo);
+                         aRequest->mIsInline, aRequest->mURI,
+                         aRequest->mLineNo);
   }
 
   aRequest->FireScriptAvailable(aResult);
@@ -552,7 +546,7 @@ nsScriptLoader::FireScriptEvaluated(nsresult aResult,
   for (PRInt32 i = 0; i < mObservers.Count(); i++) {
     nsCOMPtr<nsIScriptLoaderObserver> obs = mObservers[i];
     obs->ScriptEvaluated(aResult, aRequest->mElement,
-                         aRequest->mIsInline, aRequest->mWasPending);
+                         aRequest->mIsInline);
   }
 
   aRequest->FireScriptEvaluated(aResult);
diff --git a/content/base/src/nsScriptLoader.h b/content/base/src/nsScriptLoader.h
index 78620ad08032..9e7b8678c5d6 100644
--- a/content/base/src/nsScriptLoader.h
+++ b/content/base/src/nsScriptLoader.h
@@ -151,12 +151,25 @@ public:
    */
   void AddExecuteBlocker()
   {
-    ++mBlockerCount;
+    if (!mBlockerCount++) {
+      mHadPendingScripts = mPendingRequests.Count() != 0;
+    }
   }
   void RemoveExecuteBlocker()
   {
     if (!--mBlockerCount) {
-      ProcessPendingRequestsAsync();
+      // If there were pending scripts then the newly added scripts will
+      // execute once whatever event triggers the pending scripts fires.
+      // However, due to syncronous loads and pushed event queues it's
+      // possible that the requests that were there have already been processed
+      // if so we need to process any new requests asyncronously.
+      // Ideally that should be fixed such that it can't happen.
+      if (mHadPendingScripts) {
+        ProcessPendingRequestsAsync();
+      }
+      else {
+        ProcessPendingRequests();
+      }
     }
   }
 
@@ -214,6 +227,7 @@ protected:
   nsCOMPtr<nsIScriptElement> mCurrentScript;
   PRUint32 mBlockerCount;
   PRPackedBool mEnabled;
+  PRPackedBool mHadPendingScripts;
 };
 
 #endif //__nsScriptLoader_h__
diff --git a/content/html/content/src/nsGenericHTMLElement.cpp b/content/html/content/src/nsGenericHTMLElement.cpp
index 607c8d8e167a..cab56aae659a 100644
--- a/content/html/content/src/nsGenericHTMLElement.cpp
+++ b/content/html/content/src/nsGenericHTMLElement.cpp
@@ -849,6 +849,10 @@ nsGenericHTMLElement::GetInnerHTML(nsAString& aInnerHTML)
 nsresult
 nsGenericHTMLElement::SetInnerHTML(const nsAString& aInnerHTML)
 {
+  // This BeginUpdate/EndUpdate pair is important to make us reenable the
+  // scriptloader before the last EndUpdate call.
+  mozAutoDocUpdate updateBatch(GetCurrentDoc(), UPDATE_CONTENT_MODEL, PR_TRUE);
+
   // Remove childnodes
   nsContentUtils::SetNodeTextContent(this, EmptyString(), PR_FALSE);
 
diff --git a/content/html/content/test/test_bug300691-2.html b/content/html/content/test/test_bug300691-2.html
index e2a4e4986dd8..3497b8b29edf 100644
--- a/content/html/content/test/test_bug300691-2.html
+++ b/content/html/content/test/test_bug300691-2.html
@@ -18,8 +18,6 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=300691
 <pre id="test">
 <script type="text/javascript">
   // First, setup.  We'll be toggling these variables as we go.
-  // Note that scripts don't execute immediately when you put text in them --
-  // they wait for the currently-running script to finish.
   var test1Ran = false;
   var test2Ran = false;
   var test3Ran = false;
@@ -61,17 +59,17 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=300691
 <script class="testbody" type="text/javascript">
   /** Test for Bug 300691 **/
   $("test2").appendChild(document.createTextNode("test2Ran = true"));
-  is(test2Ran, false, "Not yet 2!");
+  is(test2Ran, true, "Should be 2!");
 
   $("test3").appendChild(document.createTextNode("test3Ran = true"));
-  is(test3Ran, false, "Not yet 3!");
+  is(test3Ran, false, "Should have run already 3!");
 
   $("test4").appendChild(document.createTextNode("test4Ran = true"));
-  is(test4Ran, false, "Not yet 4!");
+  is(test4Ran, false, "Should have run already 4!");
 
   $("test5").appendChild(document.createTextNode(" "));
   $("test5").appendChild(document.createTextNode("test5Ran = true"));
-  is(test5Ran, false, "Not yet 5!");
+  is(test5Ran, false, "Should have run already 5!");
 
   $("test6").appendChild(document.createTextNode(" "));
 
@@ -101,31 +99,27 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=300691
 <script type="text/javascript">
   // Follow up on some of those
   $("test6").appendChild(document.createTextNode("test6Ran = true"));
-  is(test6Ran, false, "Not yet 6!");
+  is(test6Ran, false, "Should have run already 6!");
 
   $("test7").appendChild(document.createTextNode("test7Ran = true"));
-  is(test7Ran, false, "Not yet 7!");
+  is(test7Ran, true, "Should be 7!");
 
   $("test8").insertBefore(document.createTextNode("test8Ran = true"),
                           $("test8").firstChild);
-  is(test8Ran, false, "Not yet 8!");
+  is(test8Ran, true, "Should be 8!");
 
   $("test9").firstChild.data = "test9Ran = true";
-  is(test9Ran, false, "Not yet 9!");
+  is(test9Ran, true, "Should be 9!");
 </script>
 <script type="text/javascript">
   is(test1Ran, true, "Should have run!");
-  is(test2Ran, true, "Should execute empty script on child append");
   is(test3Ran, false, "Already executed test3 script once");
   is(test4Ran, false,
-     "Shouldn't execute whitespace-only script on child append; should have executed it before");
-  is(test5Ran, true,
-     "By the time it tries to execute, it's got both textnodes");
+     "Should have executed whitespace-only script already");
+  is(test5Ran, false,
+     "Should have executed once the whitespace node was added");
   is(test6Ran, false,
-     "Shouldn't execute whitespace-only script on child append 2; should have executed it when it became nonempty");
-  is(test7Ran, true, "Should execute empty script on child append 2");
-  is(test8Ran, true, "Should execute empty script on child insert");
-  is(test9Ran, true, "Should execute empty script if child gets some text");
+     "Should have executed once the whitespace node was added 2");
   is(test10Ran, false, "Has an src; inline part shouldn't run");
   is(test11Ran, true, "Script with src should have run");
   is(test12Ran, true, "Setting src should execute script");
diff --git a/content/html/content/test/test_bug300691-3.xhtml b/content/html/content/test/test_bug300691-3.xhtml
index df20ff992d87..69bc2fb38fbf 100644
--- a/content/html/content/test/test_bug300691-3.xhtml
+++ b/content/html/content/test/test_bug300691-3.xhtml
@@ -30,7 +30,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=300691
 <![CDATA[
   /** Test for Bug 300691 **/
   $("test2").appendChild(document.createCDATASection("test2Ran = true"));
-  is(test2Ran, false, "Not yet 2!");
+  is(test2Ran, true, "Should be 2!");
 
   $("test3").appendChild(document.createCDATASection(""));
 ]]>
@@ -38,12 +38,10 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=300691
 <script type="text/javascript">
   // Follow up on some of those
   $("test3").firstChild.data = "test3Ran = true";
-  is(test3Ran, false, "Not yet 3!");
+  is(test3Ran, true, "Should be 3!");
 </script>
 <script type="text/javascript">
   is(test1Ran, true, "Should have run!");
-  is(test2Ran, true, "Should execute empty script on child append");
-  is(test3Ran, true, "Should execute empty script if child gets some text");
 </script>
 </pre>
 </body>
diff --git a/content/xslt/src/xslt/txMozillaXMLOutput.cpp b/content/xslt/src/xslt/txMozillaXMLOutput.cpp
index ea17bf14a866..d3e9fa655799 100644
--- a/content/xslt/src/xslt/txMozillaXMLOutput.cpp
+++ b/content/xslt/src/xslt/txMozillaXMLOutput.cpp
@@ -1020,7 +1020,6 @@ NS_IMETHODIMP
 txTransformNotifier::ScriptAvailable(nsresult aResult, 
                                      nsIScriptElement *aElement, 
                                      PRBool aIsInline,
-                                     PRBool aWasPending,
                                      nsIURI *aURI, 
                                      PRInt32 aLineNo)
 {
@@ -1035,8 +1034,7 @@ txTransformNotifier::ScriptAvailable(nsresult aResult,
 NS_IMETHODIMP 
 txTransformNotifier::ScriptEvaluated(nsresult aResult, 
                                      nsIScriptElement *aElement,
-                                     PRBool aIsInline,
-                                     PRBool aWasPending)
+                                     PRBool aIsInline)
 {
     if (mScriptElements.RemoveObject(aElement)) {
         SignalTransformEnd();