Reward: Can not get string replacement to work at all

I tried not to post anything unless I really had tried all that I knew to do, but I can't seem to get this module to work at all. I am on Drupal 6.20, I do not have any sort of caching enabled (I cleared the cache and have tried different browsers to be sure), I have enabled the Locale and Translation modules (I have also tried with these modules off), I installed the stringoverrides module and setup my strings like so:

This role will expire on !date ----> This course will expire on !date

The string I am replacing is EXACTLY as it is in the Ubercart Roles module (line 608)

$messages['uc_roles_user_expiration_message'] = t("This role will expire on !date");

I can't seem to get this or any other string replacement to work (not even the "My Account" example). I almost wonder if there is some other module which may be interfering. Could someone PLEASE help? I am willing to offer $100 to anyone who can help me figure out what is going on.

Thank you.