I have recently enabled S/MIME on BES 5.0.3 with Exchange 2010 and the only bit that doesn't seem to work is sending encrypted messages to groups. The groups have an SMTP address so when it tries to fetch the cert, it looks for that address. As a workaround I was looking at the possibility of expanding the group to get all of the members and then you would be able to encrypt the message to all recipients. Obviously this could get a bit messy with some large groups so if there is an alternative I would love to hear that too.
TIA
