diff --git a/netwerk/protocol/http/nsHttpConnectionMgr.cpp b/netwerk/protocol/http/nsHttpConnectionMgr.cpp
index b414f80b4a2b..9ad868a06491 100644
--- a/netwerk/protocol/http/nsHttpConnectionMgr.cpp
+++ b/netwerk/protocol/http/nsHttpConnectionMgr.cpp
@@ -2366,6 +2366,13 @@ nsHttpConnectionMgr::OnMsgReclaimConnection(int32_t, void *param)
             ConditionallyStopTimeoutTick();
         }
 
+        // a connection that still holds a reference to a transaction was
+        // not closed naturally (i.e. it was reset or aborted) and is
+        // therefore not something that should be reused.
+        if (conn->Transaction()) {
+            conn->DontReuse();
+        }
+
         if (conn->CanReuse()) {
             LOG(("  adding connection to idle list\n"));
             // Keep The idle connection list sorted with the connections that
diff --git a/netwerk/protocol/http/nsHttpTransaction.cpp b/netwerk/protocol/http/nsHttpTransaction.cpp
index 6867c0569b96..190558bd3257 100644
--- a/netwerk/protocol/http/nsHttpTransaction.cpp
+++ b/netwerk/protocol/http/nsHttpTransaction.cpp
@@ -1066,7 +1066,10 @@ nsHttpTransaction::Restart()
 
     // clear old connection state...
     mSecurityInfo = 0;
-    NS_IF_RELEASE(mConnection);
+    if (mConnection) {
+        mConnection->DontReuse();
+        NS_RELEASE(mConnection);
+    }
 
     // disable pipelining for the next attempt in case pipelining caused the
     // reset.  this is being overly cautious since we don't know if pipelining