rem: var charsetAtom = gCharsetConvertManager.GetCharsetAtom(compFieldsCharset); if (charsetAtom && (charsetAtom.equals("us-ascii"))) 
add: var charsetAlias = gCharsetConvertManager.getCharsetAlias(compFieldsCharset); if (charsetAlias == "us-ascii") 
context: function UpdateMailEditCharset(){  var send_default_charset = gMsgCompose.compFields.defaultCharacterSet;//  dump("send_default_charset is " + send_default_charset + "\n");  var compFieldsCharset = gMsgCompose.compFields.characterSet;//  dump("gMsgCompose.compFields is " + compFieldsCharset + "\n");  if (gCharsetConvertManager) {    var charsetAtom = gCharsetConvertManager.GetCharsetAtom(compFieldsCharset);    if (charsetAtom && (charsetAtom.equals("us-ascii")))      compFieldsCharset = "ISO-8859-1";   // no menu item for "us-ascii"  }  // charset may have been set implicitly in case of reply/forward  // or use pref default otherwise  var menuitem = document.getElementById(send_default_charset == compFieldsCharset ?                                          send_default_charset : compFieldsCharset);  if (menuitem)    menuitem.setAttribute('checked', 'true');  // Set a document charset to a default mail send charset.  if (send_default_charset == compFieldsCharset)    SetDocumentCharacterSet(send_default_charset);}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/3039a159a7704409d60a803d6e9dca639b7667f7/MsgComposeCommands.js/buggy/mail/components/compose/content/MsgComposeCommands.js