Version 4.60 introduced a new sending engine that should drastically speed up the mail sending. However, we tend to continue to support old sending engine in case someone has problems with the new one.
In order to switch your 1-2-All 4.60+ install to use old sending engine, you will have to edit the file /admin/engine.inc.php and to initialize a new variable called $GLOBALS['useOLDengine'].
In order to initialize it, add the following code to your engine.inc.php, right before the "?>" part:
