diff --git a/mozilla/extensions/transformiix/source/xslt/txMozillaTextOutput.cpp b/mozilla/extensions/transformiix/source/xslt/txMozillaTextOutput.cpp
index e44b0ffd9d6..921dc3cc893 100644
--- a/mozilla/extensions/transformiix/source/xslt/txMozillaTextOutput.cpp
+++ b/mozilla/extensions/transformiix/source/xslt/txMozillaTextOutput.cpp
@@ -49,6 +49,7 @@
 #include "nsNetUtil.h"
 #include "nsIDOMNSDocument.h"
 #include "nsIParser.h"
+#include "nsICharsetAlias.h"
 
 static NS_DEFINE_CID(kXMLDocumentCID, NS_XMLDOCUMENT_CID);
 
@@ -187,9 +188,16 @@ void txMozillaTextOutput::createResultDocument(nsIDOMDocument* aSourceDocument,
 
     // Set the charset
     if (!mOutputFormat.mEncoding.IsEmpty()) {
-        doc->SetDocumentCharacterSet(
-            NS_LossyConvertUTF16toASCII(mOutputFormat.mEncoding));
-        doc->SetDocumentCharacterSetSource(kCharsetFromOtherComponent);
+        NS_LossyConvertUTF16toASCII charset(mOutputFormat.mEncoding);
+        nsCAutoString canonicalCharset;
+        nsCOMPtr<nsICharsetAlias> calias =
+            do_GetService("@mozilla.org/intl/charsetalias;1");
+
+        if (calias &&
+            NS_SUCCEEDED(calias->GetPreferred(charset, canonicalCharset))) {
+            doc->SetDocumentCharacterSet(canonicalCharset);
+            doc->SetDocumentCharacterSetSource(kCharsetFromOtherComponent);
+        }
     }
     else {
         doc->SetDocumentCharacterSet(sourceDoc->GetDocumentCharacterSet());
diff --git a/mozilla/extensions/transformiix/source/xslt/txMozillaXMLOutput.cpp b/mozilla/extensions/transformiix/source/xslt/txMozillaXMLOutput.cpp
index 5f184e79f8f..0674c2ca568 100644
--- a/mozilla/extensions/transformiix/source/xslt/txMozillaXMLOutput.cpp
+++ b/mozilla/extensions/transformiix/source/xslt/txMozillaXMLOutput.cpp
@@ -71,6 +71,7 @@
 #include "nsIStyleSheetLinkingElement.h"
 #include "nsIDocumentTransformer.h"
 #include "nsICSSLoader.h"
+#include "nsICharsetAlias.h"
 
 extern nsINameSpaceManager* gTxNameSpaceManager;
 
@@ -738,9 +739,16 @@ txMozillaXMLOutput::createResultDocument(const nsAString& aName, PRInt32 aNsID,
 
     // Set the charset
     if (!mOutputFormat.mEncoding.IsEmpty()) {
-        doc->SetDocumentCharacterSet(
-            NS_LossyConvertUTF16toASCII(mOutputFormat.mEncoding));
-        doc->SetDocumentCharacterSetSource(kCharsetFromOtherComponent);
+        NS_LossyConvertUTF16toASCII charset(mOutputFormat.mEncoding);
+        nsCAutoString canonicalCharset;
+        nsCOMPtr<nsICharsetAlias> calias =
+            do_GetService("@mozilla.org/intl/charsetalias;1");
+
+        if (calias &&
+            NS_SUCCEEDED(calias->GetPreferred(charset, canonicalCharset))) {
+            doc->SetDocumentCharacterSet(canonicalCharset);
+            doc->SetDocumentCharacterSetSource(kCharsetFromOtherComponent);
+        }
     }
 
     // Set the mime-type
diff --git a/mozilla/parser/htmlparser/public/nsIParser.h b/mozilla/parser/htmlparser/public/nsIParser.h
index d8b1d2a1393..8edb63fae18 100644
--- a/mozilla/parser/htmlparser/public/nsIParser.h
+++ b/mozilla/parser/htmlparser/public/nsIParser.h
@@ -108,9 +108,10 @@ enum eParserDocType {
 #define kCharsetFromMetaTag             9
 #define kCharsetFromByteOrderMark      10
 #define kCharsetFromChannel            11 
-#define kCharsetFromParentForced       12
-#define kCharsetFromUserForced         13
-#define kCharsetFromOtherComponent     14
+#define kCharsetFromOtherComponent     12
+// Levels below here will be forced onto childframes too
+#define kCharsetFromParentForced       13
+#define kCharsetFromUserForced         14
 #define kCharsetFromPreviousLoading    15
 
 enum eStreamState {eNone,eOnStart,eOnDataAvail,eOnStop};