I have Ubuntu 10.04 x64 server OS and program that uses Bidirectional LPT mode (some special application that directly uses I/O). It works OK with older board. I upgraded the server to new D525MW board and I cant switch to Bidirectional mode of LPT. Bit 5 of the Control Port (base address + 2) can't be set to 1. In BIOS I selected bidirectional mode for LPT.
I changed the program to use ECP register to change LPT port to be Bidirectional.
D525MW board has bios malfunction. When changing in BIOS to Bidirectional LPT port it does not change. It is still ECP port and must use ECP register to change port functionality.