PHP Woes – 500 Internal Server Error (brand new server)

Anyone ever seen these errors, or something like it?

/usr/bin/php: error while loading shared libraries: libcom_err.so.2: failed to map segment from shared object: Cannot allocate memory

[warn] UID of script "/usr/local/apache/htdocs/index.PHP" is smaller than min_uid

[info] Executing "/home/mysite/public_html/index.php" as UID 501, GID 501

I am really not sure what the fix is to that, but I assume I have some memory settings in WHM/Cpanel set poorly?

— UPDATE:

Using the command as stated in the answer below, here is what I see when loading my user's index page (I've masked IP and username of my server):

==> /usr/local/apache/logs/error_log <==
[Sat Apr 23 17:37:18 2011] [error] [client IPADDRESS] /usr/bin/php: error while loading shared libraries: libcom_err.so.2: failed to map segment from shared object: Cannot allocate memory
[Sat Apr 23 17:37:18 2011] [error] [client IPADDRESS] Premature end of script headers: index.php
[Sat Apr 23 17:37:18 2011] [error] [client IPADDRESS] File does not exist: /home/username/public_html/500.shtml

==> /usr/local/apache/logs/suphp_log <==
[Sat Apr 23 17:37:18 2011] [info] Executing "/home/username/public_html/index.php" as UID 501, GID 501

Further, when I go directly to my IP address (with which I've just put a simple PHP Redirect to my domain name inside of the index.php…) these are the errors i get:

==> /usr/local/apache/logs/access_log <==
IPADDRESS - - [23/Apr/2011:17:40:58 -0400] "GET /index.PHP HTTP/1.1" 404 -

==> /usr/local/apache/logs/error_log <==
[Sat Apr 23 17:40:58 2011] [error] [client IPADDRESS] SoftException in Application.cpp:357: UID of script "/usr/local/apache/htdocs/index.PHP" is smaller than min_uid
[Sat Apr 23 17:40:58 2011] [error] [client IPADDRESS] Premature end of script headers: index.PHP
[Sat Apr 23 17:40:58 2011] [error] [client IPADDRESS] File does not exist: /usr/local/apache/htdocs/500.shtml

==> /usr/local/apache/logs/suphp_log <==
[Sat Apr 23 17:40:58 2011] [warn] UID of script "/usr/local/apache/htdocs/index.PHP" is smaller than min_uid

Finally…
These are empty:

• modsec_audit.log
• modsec_debug_log

and I see in suexec.log:

: uid: (501/username) gid: (501/username) cmd: redirect.cgi

and more of the same errors as already stated…