// formulario correo
function squirrelmail_loginpage_onload() {
    document.forms[0].js_autodetect_results.value = '1';
    var textElements = 0;
    for (i = 0; i < document.forms[0].elements.length; i++) {
      if (document.forms[0].elements[i].type == "text" || document.forms[0].elements[i].type == "password") {
        textElements++;
        if (textElements == 1) {
          document.forms[0].elements[i].focus();
          break;
        }
      }
    }
  }
  
  
  
  
  
  // popup
function MM_openBrWindow(theURL,winName,features) { //v2.0
  window.open(theURL,winName,features);
}

abreventana()
 <script language="javascript" type="text/javascript">
function abreventana(){
  window.open(this.href,"nuevaventana",propiedades);
  return false;
}
</script>