Can't use 32 GB in X7DBE

We recently purchased a Supermicro X7DBE+ based system with 32
gigabytes of memory, however it won't boot FC 6 (or any other 64 bit
distribution we have at hand) if more than 24 GB is installed. The
vendor confirms that they can reproduce the problem, and have
asked Supermicro for fix/work-around/comment. Does anyone here have
suggestions?

Details:

The boot loader loads, and starts the kernel, which dies with the
following message:

Kernel Panic - not syncing: Netlabel failed to initialize properly
(-17).

The kernel version is 2.6.18-1.2869. We have also tried 32-bit Ubuntu
6.10 and Suse 10.1 (kernel 2.6.16). In all cases the boot loader
functions as expected, but the kernel dies with a mysterious message.
In the case of Suse the message is:

kernel Panic: Unable to mount rootfs on known-block(1,0)
[17179571.332000]

Booting a slightly older FC6 the message is:

Dwarf2 unwinder stuck at error_exit +0x0/0x84
leftover inexact backtrace

followed by a long trace.


Daniel Feenberg
617-588-0343
feenberg isat nber dotte org

We recently upgraded the board to Fedora 7 and now it works with 32 GB.