Please help with uboot compiling on dockstar

Hi

Cutting a long story short:
I can compile uboot without errors, but as soon as i try to load the new kwb from the already installed uboot, the dockstar hangs.

i have a dockstar, i am currently running the latest uboot installed with jeffs installer.
It is version 2011.12 compiled by davygravy if i am not completely mistaken.
This version works fine, it does not support mmc however. Since i modded my dockstar to have the sd slot, i would reallz like to use it.
I am running a gentoo on this dockstar (gcc 4.6.3), i thought i could just download the 2011.12 sources, apply the patches (which i found in other threads) and compile. Compiling went fine, the dd command for aligning aswell, but as soon as i try to "go" after ther tftp, the dockstar hangs.
To make sure that it wasnt the patches, i tried a 2011.12 and 2013.01 vanilla compile, 2011.12 with the dockstar patches but withou the mmc patch ... none did work. i also tried aligned/non aligned and bin/kwb. As you can see i do not have much experience in this area, thats why i tried all combinations.

I read the forums for quite a while, and in another thread it was suggeste to use the codesourcery 2009q3 for compiling. Thing is: cant find that software anymore, and maybe i dont need it.

questions:
do i maybe miss compiler options ?
do i need a different compiler/toolchain ? i could setup a vm with the eldk ...
maybe somebody has a build environment?
maybe there is a uboot already that can boot current kernels (3.8.2) and has mmc/sd support for the dockstar?

any hints are really appreciated.
many thanks in advance

netconsole or serial console?

serial console. But i do not have jtag hardware. So the only testing i can do is trying to load the new uboot from the one on mtd0 ...