The solution was already mentioned above on how to do this with Filters.
You would need to setup two different filters and configure the profile on your Blackberry. This should only take a few minutes to setup.
Through the Web Client go to filters and add the following:
1) If
Sent To/Cc contains
me@work.com Forward messages to handheld
2) If
Sent To/Cc contains
me@bb.net Forward messages to handheld with Level 1 notification
On your BlackBerry you would setup your profile to have
Messages vibrate and
Level 1 Messages ring at max volume.
Any email sent to
would vibrate and anything sent to
would ring.