Drupbal Version
6.27

Modules
LDAP integration 6.x-1.0-beta3
CAS 6.x-3.2
CAS Attributes 6.x-3.0-beta2

When a user accesses a secure page through CAS they receive the following error:
Fatal error: Call to undefined function ldapauth_server_load() in /sites/all/modules/ldap_integration/ldapauth.module on line 666

Downgrading back to 6.x-1.0-beta2 fixed the issue.

I'm not exactly sure what the cause is but there have been a few issues posted about this same error:
https://drupal.org/node/1759012
https://drupal.org/node/1742768