diff --git a/toolkit/components/viewconfig/content/config.js b/toolkit/components/viewconfig/content/config.js
index 93b30349e2d..43bdbe44010 100644
--- a/toolkit/components/viewconfig/content/config.js
+++ b/toolkit/components/viewconfig/content/config.js
@@ -23,6 +23,7 @@
 #   Chip Clark <chipc@netscape.com>
 #   Seth Spitzer <sspitzer@netscape.com>
 #   Neil Rashbrook <neil@parkwaycc.co.uk>
+#   Mats Palmgren <mats.palmgren@bredband.net>.
 #
 # Alternatively, the contents of this file may be used under the terms of
 # either the GNU General Public License Version 2 or later (the "GPL"), or
@@ -592,18 +593,26 @@ function ModifyPref(entry)
     if (!entry.valueCol && !gPromptService.select(window, title, entry.prefCol, 2, [false, true], check))
       return false;
     gPrefBranch.setBoolPref(entry.prefCol, check.value);
-  } else {
+  }
+  else if (entry.typeCol == nsIPrefBranch.PREF_INT) {
+    var params = { windowTitle: title,
+                   label: entry.prefCol,
+                   value: entry.valueCol,
+                   cancelled: true };
+    window.openDialog("chrome://global/content/configIntValue.xul", "_blank",
+                      "chrome,titlebar,centerscreen,modal", params);
+    if (params.cancelled)
+      return false;
+    gPrefBranch.setIntPref(entry.prefCol, params.value);
+  }
+  else {
     var result = { value: entry.valueCol };
     var dummy = { value: 0 };
     if (!gPromptService.prompt(window, title, entry.prefCol, result, null, dummy))
       return false;
-    if (entry.typeCol == nsIPrefBranch.PREF_INT) {
-      gPrefBranch.setIntPref(entry.prefCol, parseInt(result.value, 10));
-    } else {
-      var supportsString = Components.classes[nsSupportsString_CONTRACTID].createInstance(nsISupportsString);
-      supportsString.data = result.value;
-      gPrefBranch.setComplexValue(entry.prefCol, nsISupportsString, supportsString);
-    }
+    var supportsString = Components.classes[nsSupportsString_CONTRACTID].createInstance(nsISupportsString);
+    supportsString.data = result.value;
+    gPrefBranch.setComplexValue(entry.prefCol, nsISupportsString, supportsString);
   }
   
   gPrefService.savePrefFile(null);
diff --git a/toolkit/components/viewconfig/content/configIntValue.xul b/toolkit/components/viewconfig/content/configIntValue.xul
new file mode 100644
index 00000000000..b57d76b6288
--- /dev/null
+++ b/toolkit/components/viewconfig/content/configIntValue.xul
@@ -0,0 +1,106 @@
+<?xml version="1.0"?>
+# ***** BEGIN LICENSE BLOCK *****
+# Version: MPL 1.1/GPL 2.0/LGPL 2.1
+#
+# The contents of this file are subject to the Mozilla Public License Version
+# 1.1 (the "License"); you may not use this file except in compliance with
+# the License. You may obtain a copy of the License at
+# http://www.mozilla.org/MPL/
+#
+# Software distributed under the License is distributed on an "AS IS" basis,
+# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+# for the specific language governing rights and limitations under the
+# License.
+#
+# The Original Code is mozilla.org configuration viewer.
+#
+# The Initial Developer of the Original Code is
+# Mats Palmgren <mats.palmgren@bredband.net>.
+# Portions created by the Initial Developer are Copyright (C) 2007
+# the Initial Developer. All Rights Reserved.
+#
+# Contributor(s):
+#
+# Alternatively, the contents of this file may be used under the terms of
+# either the GNU General Public License Version 2 or later (the "GPL"), or
+# the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+# in which case the provisions of the GPL or the LGPL are applicable instead
+# of those above. If you wish to allow use of your version of this file only
+# under the terms of either the GPL or the LGPL, and not to allow others to
+# use your version of this file under the terms of the MPL, indicate your
+# decision by deleting the provisions above and replace them with the notice
+# and other provisions required by the GPL or the LGPL. If you do not delete
+# the provisions above, a recipient may use your version of this file under
+# the terms of any one of the MPL, the GPL or the LGPL.
+#
+# ***** END LICENSE BLOCK *****
+
+<?xml-stylesheet href="chrome://global/skin/config.css" type="text/css"?>
+
+<!DOCTYPE dialog SYSTEM "chrome://global/locale/config.dtd">
+
+<dialog id="intValueDialog"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" 
+        ondialogaccept="return onIntValueDialogOK();"
+        ondialogcancel="return onIntValueDialogCancel();"
+        onload="onIntValueDialogLoad();"
+        buttonpack="center"
+        style="min-width: 29em; min-height: 10em;">
+
+<script type="application/x-javascript">
+  <![CDATA[
+    var gIntValueDialogParams;
+    function onIntValueDialogLoad()
+    {
+      gIntValueDialogParams = window.arguments[0];
+      document.title = gIntValueDialogParams.windowTitle;
+      var label = document.getElementById("label");
+      label.value = gIntValueDialogParams.label;
+      var textbox = document.getElementById("textbox");
+      textbox.value = gIntValueDialogParams.value;
+      validateIntValue();
+    }
+    
+    function onIntValueDialogOK()
+    {
+      // XXX Validate one more time because there are ways to change
+      // the text that does not trigger 'oninput' such as drag-n-drop
+      // (bug 128066) and autocomplete (bug 320462).
+      if (!validateIntValue())
+        return false;
+      gIntValueDialogParams.cancelled = false;
+      return true;
+    }
+    
+    function onIntValueDialogCancel()
+    {
+      gIntValueDialogParams.cancelled = true;
+      return true;
+    }
+    
+    function validateIntValue()
+    {
+      // We intentionally don't want to support octal/hex numbers here (bug 63117).
+      var value = document.getElementById("textbox").value;
+      var intValue = parseInt(value, 10);
+      var valid = !isNaN(value) && value == intValue.toString() && (value | 0) == intValue;
+      if (valid)
+        gIntValueDialogParams.value = intValue;
+      var okButton = document.documentElement.getButton("accept");
+      okButton.disabled = !valid;
+      return valid;
+    }
+  ]]>
+</script>
+
+
+  <hbox flex="1">
+    <hbox align="start"><image class="spaced question-icon"/></hbox>
+    <vbox flex="1">
+      <description/> <!-- dummy to get the same spacing as string value prompt -->
+      <label id="label" control="textbox"/>
+      <label value=""/> <!-- dummy to get the same spacing as string value prompt -->
+      <textbox id="textbox" oninput="validateIntValue()"/>
+    </vbox>
+  </hbox>
+</dialog>
diff --git a/toolkit/components/viewconfig/jar.mn b/toolkit/components/viewconfig/jar.mn
index d0c6af5b161..ea91c321518 100644
--- a/toolkit/components/viewconfig/jar.mn
+++ b/toolkit/components/viewconfig/jar.mn
@@ -1,3 +1,4 @@
 toolkit.jar:
 *+ content/global/config.xul              (content/config.xul) 
+*+ content/global/configIntValue.xul      (content/configIntValue.xul) 
 *+ content/global/config.js               (content/config.js)