XEmacs & Alpha/OSF 4.x

Someone at work has been asking me to help out with a bug they are seeing with XEmacs 21.4.x (most recently tested with .11 ) on their dec alpha machines. There seems to be a weird interaction with shell & gdb. If I do M-x shell, I can do ls, pwd, etc fine. When I run gdb within this shell, it starts up ok. But no matter what gdb command i enter, gdb acts like it sees it twice and prints the results twice. For example, if I enter "pwd", it will print: /home/jmiller (gdb)/home/jmiller I've tried bash/sh/csh, with or without -vanilla, mule/non mule, gcc/cc, X/tty nothing seems to have an effect. Tomorrow I may try 21.5, if I can find it, ( we don't have much in the way of internet access. ). Doing the same operations works just fine with Emacs 21.2 on the same machine. Anyone seem something like this before? I realize this isn't a very widely used/tested platform. I don't really have the time to debug this much at work, but if any one has suggestions I'm certainly will give them a try if I can. Thanks Jeff