Email addresses and E-Discovery

This has been bugging me for a while. And I'm just now going to write about it. And only because a user inadvertently brought it up.

While I was in the lunchroom, a user came in to eat; and brought her Blackberry. (We don't have a policy on Blackberrys...grrrr...a post for another day.) Anyway, one of the sales reps had emailed her back a one-word answer. "Yes." She ranted that she was sick of this rep replying one-word answers to her questions; and replying from his personal mail. She sent the original question to his corporate email address.

Back in November, the IT department was successful in changing the policy on forwarding all corporate email to personal email addresses. 90% of the users comply with this policy. First of all, management did not like the fact that official company business was being conducted with an "aol" or "hotmail" address. I didn't like it because we have no record of what is really going on. Suppose a salesrep makes a deal with a dealer giving them X% off of a future order. If the company did not comply (for whatever reason) how would we know. We can't grab aol or hotmail email. Should we get sued, we could never produce that email.

Unfortunately, it is not just salesreps that are doing this. There are some in upper management who use their personal email addresses.

So, how do you enforce this policy? I would love to hear some suggestions.