@NiLuJe
I guess you where the one who helped me in IRC as well.

I finally found time to go on with the project and get through all the hints in this post.
Unfortunately "kindle JB" and "kindlet JB" looks pretty much the same, so I was constantly on the wrong track.

solution:

• getting ixtab's kindle jailbreak
• getting the KUAL sources
• taking a close look how the jailbreak was used
• applying it to me
• tadaaa

If anybody else runs into similar problems:
As soon as I cleaned up my code and got through all left problems, I'm going to write a small tutorial about how to get unrestricted access

greets