Finding legit e-mails in queue of thousands of backed up messages and DNRs

A recent systems problem on our Win2000 Exchange server had resulted in a unit crash. When it was restored (no, not by me), somehow a setting change resulted in permitting our server to relay outside (i.e. spam) traffic. Because this resulted in an unbelievable number of DNR messages coming back to our server, several hundred queues have been created by the system, and a large number of them have hundreds or thousands of backed up messages and DNRs.

We have resolved the relay issue and are left with the bottleneck relating to the queues. Do you know of a way to search the queues for legitimate messages (i.e. a wild card search for messages with our domain name) and then extract them and delete the rest? Or is there a third-party software source that can accomplish this?
The e-mail messages should be sitting in one of the folders under \Inetpub\mailroot, such as the Badmail or Queue folders. These are SMTP messages which are in text format. Therefore, you can use the Windows search feature to search for and identify messages with particular words or strings in them.