I’m running
Kernel Version 2.6.18-53.1.14.el5 (SMP)
Distro Name CentOS release 5 (Final)
Asterisk (Ver. 1.4.22
If I want to run 2 companies, one is a split from my existing company, I understand about creating trunks that will go to a different IVR based on the number the caller dialed, but do I then need to create extensions that are entirely different from those I currently use? Any tricks to work around this or other potential pitfalls I need to watch out for?
I’ve had this fantasy for years. Two on one. Oh, yeah…
wait. Phones. 
Yeah, you have to worry about extensions, but that’s usually pretty easy: use four digit extensions with different starting numbers for each. That should keep you OK for most things. The second thing to worry about that I can think of off the top of my head is that your “0” destination is going to go to the same place.
Just think through your call flow real well and you should be fine. Try to utilize the CID prefix to your advantage to notify receptionists of which company the call is coming in for.
Test everything obsessively. Good luck.
I thought so. It just seems like this should be easier to do. Thanks for the late night feedback.