I have Call Manager 5.1.3, and I do not know how to configure the Conference Feature?
ok, this is a very simple task. I hope you have at least the most basic concepts for CUCM. If not, start reading the guide before anything else
Cisco Unified CallManager Administration Guide, Release 5.1(3)
All you need to do is to configure the MRGL with the CFB in it. That's it.
If you have the default softkey templates and default values for calls per line and busy trigger, then, the above is all you need.
Even if you don't configure a single MRG and leave all in the default MRG you can start doing conferences. Though it's not the best practice.
SW CFB only handles G711, again, if everything is set to default you should already be using it.
if this helps, please rate