I think the big difference is WHAT is being load balancing.
What is a Windows cluster balancing? In a domain, it's really the user registry, right?
With a
J2EE application, you're workload managing somethign totally different- you're workload managing web based requrest for resources, and also need to replicate users sessions and data across clusters. An OS would not be capable of doing this.
Plus, things like sticky sessions, which J2EE requires, isn't even in the realm of a Windows or Linux OS.
The differences are just too significant.
Interesting question though.
-Cameron McKenzie