List of Linux Distributions with Port Multiplier Support
Update: Kernel versions after: 2.6.15 claim to support port multiplier. The information below is for reference only.


Note:
PATCHES CONTAINED IN THIS ARCHIVE ARE CONSIDERED EXPERIMENTAL
AND MAY CAUSE MASSIVE DATA LOSS.  YOU'VE BEEN WARNED.
Do NOT use these patches on critical production systems.  Make full backup of all data of any importance, we won’t accept 
responsibility for your data loss.

Ubuntu 6.06 LTS Server Edition
Kernel Version: 2.6.15-23-server
Fedora Core 5 Kernel Version: 2.6.15-1.2054_FC5