Can I have in one IBM ISeries partitions of HDD with diferent operating systems, example:
1 partition i5/os 2 partition AIX
Like Abel said, this should be on Server Fault. Since it'll probably just get moved. I'll still answer here.
Yes, you can do that though I am not sure exactly how. Your best bet is to contact your business partner for costs and how to proceed. Another resource would be MIDRANGE-L at midrange.com, I am pretty sure there are others that have done this.