[syslinux] problem booting msdos with memdisk

[Uli Raich]

Hi all,
I try to boot an msdos system using pxelinux and memdisk on my PC engines Wrap-2.c card and I have problems with it
This is what I see:
PXELINUX 3.11 Debian-2006-03-16  Copyright (C) 1994-2005 H. Peter A
boot: msdos
Loading memdisk....
Loading images/msdos/msd622bd.dosim.........................
Ready.
dp83815: Setting full-duplex based on negotiated link capability.
MEMDISK 3.11   Copyright 2001-2005 H. Peter Anvin
e820: 0000000000000000 00000000000a0000 1
e820: 00000000000f0000 0000000000010000 2
e820: 00000000fff00000 0000000000100000 2
e820: 0000000000100000 0000000007f00000 1
Ramdisk at 0x07d61000, length 0x00168000
command line: initrd=images/msdos/msd622bd.dosim BOOT_IMAGE=memdisk
Disk is floppy 0, 1440 K, C/H/S = 80/2/18
Total size needed = 1899 bytes, allocating 2K
Old dos memory at 0x9fc00 (map says 0xa0000), loading at 0x9f400
1588: 0xffff  15E801: 0x3c00 0x06d6
INT 13 08: Failure, assuming this is the only drive
old: int13 = f000ac5e  int15 = f000a60a
new: int13 = 9f400008  int15 = 9f400290
Loading boot sector... booting...

from then on nothing happens.
Can this be a BIOS problem (PC engines uses its own TiniBios) or what else may I try?
Thanks Uli