Notes/Exchange Dist List Problem

[maxmanbug]

I know that this is more complicated than it seems but here goes. We are a Notes r 6.and Exchange 2003 shared environment. We have one server connecting our environments that has a copy of the Notes address book on it. Here is our problem: A Distribution Group is created in Notes with a corresponding contact in the Exchange Global Address Book. When a Notes user sends to the list all users receive the message. When an Exchange user sends to the list it goes to the Notes environment which then expands the list and tries to send to the Exchange users (valid addresses) but, NONE of the Exchange people receive the message and no delivery failure message is delivered. They all end up in the dead file. Anyone have any ideas?