fsiddiqi, I have had similar problem in the past but can't recall exactly what I did to fix it. One thing you might check (and I'm no expert with this), is the php memory limit. I added something like...

ini_set('memory_limit',  '16M');

...to my sites/default/settings.php file.

There maybe a difference in this setting between your test server and production server. If I'm way off just ignore me