You are tough guy like Di Luca
just insert a few lines into include/checklogin.php line 43
$member_handler =& xoops_gethandler('member');
$myts =& MyTextsanitizer::getInstance();
if( strstr( $_POST['uname'] , '@' ) ) {
list( $uname ) = $xoopsDB->fetchRow( $xoopsDB->query( "SELECT loginname FROM ".$xoopsDB->prefix('users')." WHERE email='".$myts->addSlashes($_POST['uname'])."'" ) ) ;
}
// Place here the Auth class calls
//**** BEGIN AUTH ****
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(2007-6-4 edited) fixed from uname -> displayname