That's just the thing. The users are receiving the emails that mirror the following (after trying the OTA "Enterprise Activation"):
This message is used to carry data between the BlackBerry Handheld and an associated server. Please do not delete, move or respond to this message - it will be processed by the server.
I'm assuming that this message (above) is the email that you are talking about? However, the activation is still NOT completing and it will keep saying "Retrying....Retrying...Retrying"