I'm not sure about the current status of this issue, but I think, there were some plans to support all codepages available to the OS, which would solve this kind of problems, I guess. (see e.g. http://forum.pspad.com/read.php?6,35861,36465#msg-36465)
-- <http://forum.pspad.com/read.php?2,44176,44177> PSPad freeware editor http://www.pspad.com
