Support ticket system???
 

Hi everybody ))
Need your help

Anybody knows good support ticket system software.
I need to organize members support of a pay site.
I don't have extraordinary requirements. But there should be the ability to answer tickets via that system and by e-mail also. In the e-mail there should be link to the history.
It is also appreciated if that system has a good support as well )). So if something is wrong with the software I can fix it easy and fast.

Thx you in advanced ))