@Hitman
The original 4gb patch only addressed 64 bit systems. Not sure about privateer's version. It not so much makes the OS see all your installed ram, rather it makes the .exe use more than it normally would (can't remember how much that is sorry), hope this answers your question.
EDIT: I actually found some quite useful info about this and the 3 GB patch some time back, read my post here;
http://www.subsim.com/radioroom/show...54&postcount=6
Best regards.
Fubar2Niner