dunno if its effecting, but have a look at the place of your slashes that uncomment that row ??
//if ($xoopsConfig['debug_mode'] == 1) {
error_reporting(E_ALL);
//}

the } stands alone at the end ? try uncommenting the whole,
otherwise it could effect other statements...
..
//
if ($xoopsConfig['debug_mode'] == 1) {
error_reporting(E_ALL);
}
//

hope its helpful...
michael