guldener.net

Jailbreaking my old Iphone 3GS 4.1 (05.14.02) was finally successful.

Tool used: http://www.greenpois0n.com/

First tries under Windows did not do it.
Try under Linux and it's ok. (sudo!)

1. Download greenpois0n here: http://www.greenpois0n.com/
2. To run the tool under 64bit linux, it could be a little tricky.
   you may need some 32bit libs. I suggest using getlibs to install the libraries you need in 32bit versions. This is the command:
   sudo getlibs /path/to/greenpois0n_x86
3. Start your Iphone in DFU-Mode:
   1. Turn off the phone