Suggestions to manage semi-structured email bounces?

Question

The company I work for sends a lot of emails, and in return we get a lot of bounces.
We currently don't have a good way of sorting them and help us archive the routine ones while putting the important ones in front of human eyes.
From a format of view these email bounces are not well structured, but there are some sort of patterns.
There is a preliminary system that is being worked on but it is becoming an unmanagable collection of complicated regular expressions.
I convinced my company to let me take home a portion of the bounces, and I am hoping to find a better way to handle them in my free time. It's both an opportunity to learn something interesting and do something valuable.
How would you approach this problem? Is there a class of methods or algorithms that are a good fit for this situation?

Thank you.