Blackberries and recalled messages

We have Exchange 03, Outlook 07 and some users with Blackberries. My
question is this, when a user sent an email with an attachment to a group of
users, they all got a copy of the original message, however when she tried a
recall .. she got a "failed" message and one of the users got the recall via
BB, but not in her Outlook and none of the other users got the recall
message. Is that an issue on the sender's end of the receiver's? I believe
this is an OL issue as it was sent via OL 07, and most affected users don't
even have BBs.

thanks so much ...