rem: gSmtpUsername.removeAttribute("disabled"); gSmtpUsernameLabel.removeAttribute("disabled"); 
add:   if (!checkbox.disabled) { gSmtpUsername.removeAttribute("disabled"); gSmtpUsernameLabel.removeAttribute("disabled"); } 
context: function onUseUsername(checkbox, dofocus){    if (checkbox.checked) {        gSmtpUsername.removeAttribute("disabled");        gSmtpUsernameLabel.removeAttribute("disabled");        if (dofocus)            gSmtpUsername.focus();        if (gSavedUsername && gSavedUsername != "")            gSmtpUsername.value = gSavedUsername;    } else {        gSavedUsername = gSmtpUsername.value;        gSmtpUsername.value = "";        gSmtpUsername.setAttribute("disabled", "true");        gSmtpUsernameLabel.setAttribute("disabled", "true");    }}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/b8e380d020d466d68a4597e0838d1371a056982d/smtpEditOverlay.js/clean/mailnews/base/prefs/resources/content/smtpEditOverlay.js