[syslinux] mboot hangs at MPI

[Lin Salisbury]

I'm attempting to PXE boot a XEN dom0 kernel version 2.6.16, xen version
3.0.2-2.  I've built syslinux-3.20-pre8 from source and am using the
following config:

DEFAULT mboot.c32 xen-3.0.2-2.gz dom0_mem=258048 --- vmlinuz-2.6.16-xen0 ro
console=ttyS0 root=/dev/sda1 --- initrd.img

Where initrd.img is my own custom initrd that I've built to do some
pre-setup before booting to the real root on sda1.  The problem is that
everytime I try and boot I get to this line and it just hangs:

Booting: MBI=0x00010120, entry=0x00100000

I found references to this problem in the archives
(http://syslinux.zytor.com/archives/2006-March/006654.html )
and made sure that the memset of the regs_in was happening, and that is
being done in 3.20-pre8 (hence the reason I'm even using it).  I found some
references to using particular versions of gcc, I'm currently using
3.4.4could this be a potential issue?

I'm hoping that once I get past the mboot.c32 issues and actually get into
my initrd.img everything should be pretty straight forward from there but
this multiboot stuff over PXE is quite the mind-bender:)  I'm hoping
somebody has had similar problems and could at least point me in the general
direction?

Also, some other info that may be helpful.  The hardware is a Dell PowerEdge
1850 with this signature for the PXE firmware:

Initializing Intel(R) Boot Agent GE v1.2.26
PXE 2.1 Build 084 (WfM 2.0)

Thanks very much for *any* advice on this problem.

Lin Salisbury