hmmm ... older boxes will run 4.x and 3.x (MCA boxes), but if your
asking if you can run 4.x or 3.x on say a p5 running some emulation
software, then the <simple> answer is NO.

there are some projects out there that that emulate the powerpc
(http://pearpc.sourceforge.net/faq.html) but have not got very far with
AIX testing, but there is the possibility to do this on intel or power
with pearpc .. its just not evolved that far .. why not email them and
offer to help out with testing.

Rgds
Mark Taylor