I currently have REL4 32 bit and I want to move up to RHEL IA64. I am currently planning to purchase new hardware. I want to upgrade my 32 bit system to a 64 bit system by using RPM's. Has any body done anything like this before?

Thanks

I don't how you would do this unless the host has an IA64 chip already. You do know that it is the chip that makes it 64 bit rather than 32 bit I hope.

In any event I'd recomment a full backup and full install of the new version rather than an attempted upgrade. My experience with upgrades is that no matter how well you plan them:
1) There is always something you miss - the effort never seems to be worth it.
2) Upgrades leave tons of junk that you no longer need on the system in all sorts of directories - you never truly clean them out.

I am going to purchase a 64 bit processor. Your point is well taken. Can you point me in the direction about how to build installable version of RHEL4 AS from RPMS?

RHEL 4 AS? Don't you have access to RedHat Network? This is the commercial package.

That site is: https://rhn.redhat.com/index.pxt

Anyway I don't know whether they have a 64 bit but if so you can likely find out about it there.

I would suggest looking into the EM64T series of processors. It will greatly ease this sort of transition, because it will do both 32 and 64 bit.