Can Unity 4.2.1 import users directly from CCM 5 with AXL like Unity Connection server??
If not, what's the easiest way to import thousand of users into Unity 4.2.1 server??
No, Unity does not have that capability only CUC with CCM 5.
The easiest way to import a bunch of users into Unity at once would be to use Cisco Unity Bulk Import (CUBI):