I'm trying to set up a medium sized Drupal 7 website on my miniserver but I keep getting a 500 error message. This is what I found in Apache's error log:

[Wed Sep 12 15:02:04 2012] [notice] SSL FIPS mode disabled
[Wed Sep 12 15:02:04 2012] [warn] No JkShmFile defined in httpd.conf. Using default /usr/local/apache/logs/jk-runtime-status
[Wed Sep 12 15:02:04 2012] [notice] Apache/2.2.22 (Unix) mod_ssl/2.2.22 OpenSSL/1.0.0-fips mod_auth_passthrough/2.1 mod_bwlimited/1.4 FrontPage/5.0.2.2635 mod_jk/1.2.35 configured -- resuming normal operations
[Wed Sep 12 15:02:07 2012] [error] [client 89.16.136.28] /usr/bin/php: error while loading shared libraries: libkrb5support.so.0: failed to map segment from shared object: Cannot allocate memory
[Wed Sep 12 15:02:07 2012] [error] [client 89.16.136.28] Premature end of script headers: index.php
[Wed Sep 12 15:02:07 2012] [error] [client 89.16.136.28] /usr/bin/php: error while loading shared libraries: libkrb5support.so.0: failed to map segment from shared object: Cannot allocate memory
[Wed Sep 12 15:02:07 2012] [error] [client 89.16.136.28] Premature end of script headers: index.php
[Wed Sep 12 15:02:07 2012] [error] [client 89.16.136.28] File does not exist: /home/brighton/public_html/favicon.ico
[Wed Sep 12 15:02:07 2012] [error] [client 89.16.136.28] /usr/bin/php: error while loading shared libraries: libkrb5support.so.0: failed to map segment from shared object: Cannot allocate memory
[Wed Sep 12 15:02:07 2012] [error] [client 89.16.136.28] Premature end of script headers: index.php

I contacted support and they just told me I should just upgrade my package (right not I have a 512Mb account), but I am not sure if I'm buying it... even if I'm trying to access a file which only contains phpinfo(); I still get the 500.

Any help would be much appreciated, and if there's need of any other information please let me know and I'll update the question. I compiled apache with tomcat because I intend to use Solr... not sure if this is relevant or not.