Jon, thanks for the input. I read the thread you suggested. Just for kicks I processed the "rpm -qa | greg ^php" command and it returned these modules:
php-ldap-4.0.6-10.arvin.rh7.1
php-4.0.6-10.arvin.rh7.1
php-imap-4.0.6-10.arvin.rh7.1
php-mysql-4.0.6-10.arvin.rh7.1
I also ran the phpinfo() function and imap, sql, and ldap are all supported.
The PHP upgrade went very smoothly thanks to Dan's HowTo (
http://www.familybrown.org/howtos/php-upgrade-howto-2.html).
However, the problem still remains. I'm not able to receive incoming emails. I was looking into upgrading IMP to version 3.0 in hopes that it would solve the problem but I have not found any information on how to do this. Either way, I need to get this resolved... my only other option is to rebuild my server which is not something I want or can do easily. Any and all help is greatly accepted. Thanks. - Trevor