diff --git a/mailnews/base/prefs/resources/content/AccountManager.js b/mailnews/base/prefs/resources/content/AccountManager.js
index 508ea18bd25..a2b200944c8 100644
--- a/mailnews/base/prefs/resources/content/AccountManager.js
+++ b/mailnews/base/prefs/resources/content/AccountManager.js
@@ -761,10 +761,21 @@ function onPanelLoaded(pageId) {
   pendingPageId = null;
 }
 
-
 function loadPage(pageId)
 {
-  document.getElementById("contentFrame").setAttribute("src","chrome://messenger/content/" + pageId);
+  var chromePackageName;
+  try 
+  {
+    // we could compare against "main","server","copies","offline","addressing",
+    // "smtp","advanced", and "fakeaccount" first to save the work, but don't
+    // as some of these might be turned into extensions (for thunderbird)
+    chromePackageName = accountManager.getChromePackageName(pageId.split("am-")[1].split(".xul")[0]);
+  }
+  catch (ex) 
+  {
+    chromePackageName = "messenger";
+  }
+  document.getElementById("contentFrame").setAttribute("src","chrome://" + chromePackageName + "/content/" + pageId);
 }
 
 //
diff --git a/mailnews/base/public/nsIMsgAccountManager.idl b/mailnews/base/public/nsIMsgAccountManager.idl
index 57b5bc77415..acf6e8be6e1 100644
--- a/mailnews/base/public/nsIMsgAccountManager.idl
+++ b/mailnews/base/public/nsIMsgAccountManager.idl
@@ -192,6 +192,8 @@ interface nsIMsgAccountManager : nsISupports {
 
   // force account info out to prefs file
   void saveAccountInfo();
+
+  string getChromePackageName(in string aExtenstionName);
 };
 
 
@@ -203,7 +205,8 @@ interface nsIMsgAccountManager : nsISupports {
 [scriptable, uuid(9ce9fc76-1dd1-11b2-8da2-bf6b98b4c537)]
 interface nsIMsgAccountManagerExtension : nsISupports
 {
-    readonly attribute string name;
+    readonly attribute string name;   // examples:  mdn
 	boolean showPanel(in nsIMsgIncomingServer server);
+	readonly attribute string chromePackageName;  // example:  messenger, chrome://messenger/content/am-mdn.xul and chrome://messenger/locale/am-mdn.properties
 };
 
diff --git a/mailnews/base/src/nsMsgAccountManager.cpp b/mailnews/base/src/nsMsgAccountManager.cpp
index 76d678adc45..a0c058d6c8a 100644
--- a/mailnews/base/src/nsMsgAccountManager.cpp
+++ b/mailnews/base/src/nsMsgAccountManager.cpp
@@ -79,6 +79,8 @@
 #include "nsIImapIncomingServer.h" 
 #include "nsIImapUrl.h"
 #include "nsIMessengerOSIntegration.h"
+#include "nsICategoryManager.h"
+#include "nsISupportsPrimitives.h"
 
 #define PREF_MAIL_ACCOUNTMANAGER_ACCOUNTS "mail.accountmanager.accounts"
 #define PREF_MAIL_ACCOUNTMANAGER_DEFAULTACCOUNT "mail.accountmanager.defaultaccount"
@@ -2342,3 +2344,49 @@ nsMsgAccountManager::SaveAccountInfo()
   return m_prefs->SavePrefFile(nsnull);
 }
 
+NS_IMETHODIMP
+nsMsgAccountManager::GetChromePackageName(const char *aExtenstionName, char **aChromePackageName)
+{
+  NS_ENSURE_ARG_POINTER(aExtenstionName);
+  NS_ENSURE_ARG_POINTER(aChromePackageName);
+ 
+  nsresult rv;
+  nsCOMPtr<nsICategoryManager> catman = do_GetService(NS_CATEGORYMANAGER_CONTRACTID, &rv);
+  NS_ENSURE_SUCCESS(rv,rv);
+
+  nsCOMPtr<nsISimpleEnumerator> e;
+  rv = catman->EnumerateCategory(MAILNEWS_ACCOUNTMANAGER_EXTENSIONS, getter_AddRefs(e));
+  if(NS_SUCCEEDED(rv) && e) {
+    while (PR_TRUE) {
+      nsCOMPtr<nsISupportsCString> catEntry;
+      rv = e->GetNext(getter_AddRefs(catEntry));
+      if (NS_FAILED(rv) || !catEntry) 
+        break;
+
+      nsCAutoString entryString;
+      rv = catEntry->GetData(entryString);
+      if (NS_FAILED(rv))
+         break;
+
+      nsXPIDLCString contractidString;
+      rv = catman->GetCategoryEntry(MAILNEWS_ACCOUNTMANAGER_EXTENSIONS, entryString.get(), getter_Copies(contractidString));
+      if (NS_FAILED(rv)) 
+        break;
+
+      nsCOMPtr <nsIMsgAccountManagerExtension> extension = do_GetService(contractidString.get(), &rv);
+      if (NS_FAILED(rv) || !extension)
+        break;
+      
+      nsXPIDLCString name;
+      rv = extension->GetName(getter_Copies(name));
+      if (NS_FAILED(rv))
+        break;
+      
+      if (!strcmp(name.get(), aExtenstionName))
+        return extension->GetChromePackageName(aChromePackageName);
+    }
+  }
+  return NS_ERROR_UNEXPECTED;
+}
+
+
diff --git a/mailnews/base/src/nsMsgAccountManagerDS.cpp b/mailnews/base/src/nsMsgAccountManagerDS.cpp
index 25819a0c5e6..e3bbf60ab6b 100644
--- a/mailnews/base/src/nsMsgAccountManagerDS.cpp
+++ b/mailnews/base/src/nsMsgAccountManagerDS.cpp
@@ -403,10 +403,19 @@ nsMsgAccountManagerDataSource::GetTarget(nsIRDFResource *source,
             // make sure the pointer math we're about to do is safe.
             NS_ENSURE_TRUE(sourceValue && (strlen(sourceValue) > strlen(NC_RDF_PAGETITLE_PREFIX)), NS_ERROR_UNEXPECTED);
 
-            nsCAutoString bundleURL;
-            bundleURL = "chrome://messenger/locale/";
-            bundleURL += "am-";
+            nsCOMPtr<nsIMsgAccountManager> am =
+              do_QueryReferent(mAccountManager, &rv);
+            NS_ENSURE_SUCCESS(rv, PR_FALSE);
+            
             // turn NC#PageTitlefoobar into foobar, so we can get the am-foobar.properties bundle
+            nsXPIDLCString chromePackageName;
+            rv = am->GetChromePackageName((sourceValue + strlen(NC_RDF_PAGETITLE_PREFIX)), getter_Copies(chromePackageName));
+            NS_ENSURE_SUCCESS(rv,rv);
+
+            nsCAutoString bundleURL;
+            bundleURL = "chrome://";
+            bundleURL += chromePackageName;
+            bundleURL += "/locale/am-";
             bundleURL += (sourceValue + strlen(NC_RDF_PAGETITLE_PREFIX));
             bundleURL += ".properties";
 
diff --git a/mailnews/extensions/mdn/src/mdn-service.js b/mailnews/extensions/mdn/src/mdn-service.js
index 90c5ff9b234..647ea0a627b 100644
--- a/mailnews/extensions/mdn/src/mdn-service.js
+++ b/mailnews/extensions/mdn/src/mdn-service.js
@@ -36,6 +36,7 @@ function MDNService()
 {}
 
 MDNService.prototype.name = "mdn";
+MDNService.prototype.chromePackageName = "messenger";
 MDNService.prototype.showPanel =
 
 function (server)
diff --git a/mailnews/extensions/smime/src/smime-service.js b/mailnews/extensions/smime/src/smime-service.js
index b0651469575..0f842903741 100644
--- a/mailnews/extensions/smime/src/smime-service.js
+++ b/mailnews/extensions/smime/src/smime-service.js
@@ -36,6 +36,7 @@ function SMIMEService()
 {}
 
 SMIMEService.prototype.name = "smime";
+SMIMEService.prototype.chromePackageName = "messenger";
 SMIMEService.prototype.showPanel =
 
 function (server)