grails, drools, and ticket / issue trackers, iTicket

I need to integrate a ticketing system into my grails Web application, so that those running the small company can easily handle customer needs / complaints, etc., tying that in directly with their users. When I searched for a plugin or built application, I found:

• drools plugin, small ticketing capability/example, which after having an installation bug led me to
• drools-gorm plugin, and then also briefly reviewing
• iTicket, which I'm just currently shying away from because of its inclusion of roles management but no mention of Spring Security Core and UI, which is what I'm using for role management
• article on building a small issue tracker with Grails

I don't have a lot of problem domain knowledge with 开发者_C百科ticketing systems, and so I'm wondering if someone whose gone down this road before or knows ticketing system domain modelling & rules engines in general can give a few comments. E.g. are flexible rules engines very important for ticketing systems, or is this only for heavier weight applications? What kinds of other general things can one do with grails plus drools, that might be useful? Alternatively, the opposite, is staying light weight best, because these things often turn out to be very "custom" in this arena.

Your experience is appreciated.

Thanks