Warnings on Display – path issue?

I have installed WordPress on a virtual dedicated server. The domains are setup using Addon Domains in cPanel. WordPress is installed through Fantastico. For some reason, a path to the parent domain root is being written and continues to appear as a warning on the blog screen. Here’s the message I’m getting:
Warning: preg_match(): Compilation failed: nothing to repeat at offset 1 in /home/parentusername/public_html/installdomain.com/wp-includes/classes.php on line 1549

I’ve changed the names to protect the innocent, but this is the general path to the root of the parent hosted domain.

Can anybody tell me where this would exist on the install? We’ve reinstalled this several times and continue to come up with the same thing. We’ve installed it to installdomain.com and installdomain.com.parentdomain.com and received the same results. It seems fine at first, then as soon as I begin to customize the options, Writing and reading settings, etc.. the warnings come back up.

Help! Appreciate any assistance with this. My hosting support really isn’t making any progress on this.

Thanks,
Shawn