Hey Matt, I was looking thru the imp mailing list archives and noticed your problem, I had the exact same problem.
I know nothing about php3 programming but I had an old 2.2.3 imp system still up. So I peeked at the help.php3 and compared it to the new horde one. They were different from each other on line 33. So I edited the one line: /usr/share/horde/help.php3 line 33 to look like this: require '/etc/' . $module . '/lang.php3'; Give that a try if your're still having the problem. If you got the error fixed some other way, can you please tell me? I don't know if its an error in the help.php3 file or something else. but anyway, the problem has seemed to go away. HTH, Cheers, Mike