rem: if (!messageUri) return false; else return (messageUri.substring(0,14) == "imap-message:/"); 
add: return (/^imap-message:/.test(messageUri)); 
context: function IsImapMessage(messageUri){    if (!messageUri)       return false;    else      return (messageUri.substring(0,14) == "imap-message:/");}
meta: 5872	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5872/cbb05359cfa659c0cd4b81f0b0d5ee9ea5b02e21/mailWindowOverlay.js/buggy/mailnews/base/resources/content/mailWindowOverlay.js