Everyone fears WebSphere. I've tried to run it twice (albeit not in the last 6 months) and both times I gave up before I even got to the 'deploy application' stage.
To get WebSphere running I believe you need a small squadron of highly paid IBM consultants, and a battery of seriously large IBM hardware.
If you have that (and can handle the very old standards compliance!), I believe it's quite a nice server ;) [PSquad's Corner] via... [rebelutionary]
Hi there! I'm a <edit>moderately well-</edit>paid IBM consultant!
To get Websphere 4.0 running, you'll need a good mid-range Linux (or some other OS if you're heathen) box, and a copy of the appropriate Redbook. Redbooks are way cool - this one is about two inches thick when you print it out, and has step-by-step installation/deployment instructions.
Oh, and you'll also need a rather significant five- or six- figure sum to pay for the software licenses.