[exim] submission rewrite question..

In our acl_check_rcpt we have:

accept authenticated = *
control = submission/domain=

and there are things in the logs like this:

2010-02-12 11:52:32 [58655] 1Nfykq-000FG3-H4
"name.whatever@???" from env-from rewritten as
"user@???" by submission mode


While this is generally what we want.. we do have a few times that we
would like this to not happen..

We have a 'work' account that we have support@ info@ etc.. that gets
sorted into folders support/ info/ etc..

b/c we authenticate as workaccount@??? it rewrites our
support@ or info@ as who/what we authenticate as..

How can we tell exim to not do this for certain names/emails?

Thanks in advance.