If the work email is not on a BES so something like...exchange server, POP3 server etc.....
you can try to delete the account completely from the BIS
a.) from the phone -- email setup
b) from the web -- BlackBerry Internet Service
b1) if you havent created an account here create one
after you delete re-add the work account....
If you happen to be on the BES have your IT re-activate your BES activation..
also have any of your server settings changed? incoming outgoing server names etc?