[TxMt] Changing Tab-Behavior

Hi, I'm new to the list, so please forgive me, if this has being asked before. Is it possible to change the tab behavior of TextMate? For example I find it strange that single line intending to the right works correctly (using tabs), but if you try to tab back to the left site, it is using spaces instead of tabs.

It would also be great to change the behavior of multi line tabbing. I'm so used to use the tab key to intend to the right and "apple key" together with the tab key to move lines to the left. But if I do that, the lines I would like to intend, are deleted.

(I hope you understand what I mean.. sorry for my english)

Other then that I really like TextMate.

Kind Regards, Andy Switzerland