Does the userApp in IDM3 care whether it's on a SLES9 server or an OES
Linux server?

(Yes, I know OES Linux is SLES 9, but it's got other stuff on it too)

Does it require eDir On THAT SLES server? or can it just point to a
replica via LDAP?

If it needs eDir, does it also need replicas on it?