Please Help. Active Directory Plugin

I've successfully bound both an XServe and MBP both running 10.5.4 to our Active Directory and everything appears to work initially. However, after about 5 Minutes the Directory Utility reports that the Active Directory server is no longer responding and from that point on the AD plugin never works again. Where can I go to look for diagnostic information? I've been working on this for quite a while and it's really frustrating.