Still advising caution
I'm still advising caution in using this system for several reasons:
1) If they're already in a ticketing system, then the ticket system has the latest information, and generally has some way of sorting out this information without you having to do much. Some even have the ability to use some form of macro capability so you can further customize it for your needs. Also, if your mail includes updated versions of these tickets, will you be updating your copy?
2) These tickets are most likely not next actions, so sorting them in a database is just going to give you a sorted mass of items that need completion, not do-able next actions. Are you planning on inserting next action steps into this database as well?
3) Does the e-mail contain all of the text that you require, or will you spend your time trying to gather all of the required fields?
4) Are you going to put the entire text of the mail into a BLOB, or are you going to take the effort to parse out the mail into individual fields? If you are going to make the BLOBs, is your database able to search those BLOBs quickly and efficiently?
5) You mention that you're looking for a *nix solution. Are both the ticket tracking and mail systems using Windows, or are there *nix alternatives for accessing both that don't suck? (I know that sometimes the *nix clients of software are very crippled when compared to the Windows version).
6) Is there an API you might be able to use instead to garner information from the ticket system, rather than using mail as the protocol? Mail is terribly unreliable, and if an alternative exists, you may want to explore it.
It's simple to think "Well, I'll just stuff it all into a database, since I can retrieve it all from a database", but even the most skilled SQL jockeys will require some structure to make sense out of the data going into the database. Are you prepared to care and feed for an additional system in case something changes upstream? Creating systems takes planning, and the quick 1 hour hack you do today could become the 4-8 hour maintenance headache later on.
The most important part about all of this, outside of the technical questions, is that you end up with a list of next actions to complete these tasks. Without them, you will have moved your mail spool of undoable mail into a database of undoable rows. How do you plan to seperate next actions so that you'll see them when you need to see them, and can create them quickly in under 30 seconds. If it's not that quick, you're not going to be using your system effectively, and you'll likely leave your entire pile of mails in the database as your next action list. That's not going to solve any problem you might have.
That said, if you're still interested in doing this, I will do my best to help out. Please understand my reasons for not posting posting solutions thus far are because I can see several pitfalls with this approach (I've thought about them myself, and I've used several systems that seemed like they were effective at the time, and have proved otherwise).
Hope this helps!