Thanks to postings of Dinesh Nair and Raphael Maunier i 'm able to
boot M0n0wall from a CF card on a Nexcom 1041, without the the fatal
"The device that contains the config file (config.xml) could not be found".
Bios changes are:
Load Optimized Default --> Save & Exit --> Reboot
Enter bios again by console or vga.
Standard Cmos Features --> IDE Secondary Master -->
Access Mode [CHS]
I also disabled de ACPI function in Power management setup but this is
not needed for a clean boot.
Have a nice day. :-)