We are currently running CallManager 11.0 and have a couple of questions:
1) Our DID number are 284-xxxx and 457-xxxx. Our directory number are setup as 5-digit extensions - 4xxxx and 7xxxx. Who converts the 7-digit number to 5-digits? Our phone line carrier (ATT)? CallManager?
2) We are planning on getting an 800 number - 800-222-3333. Do we just enter the directory number into CallManager as 23333?
Start by running debugs in your GW to find out what you get from your telco, that will give you the answer to #1, if you want to know the call flow in CUCM, use DNA or just look at your config/dial plan.
#2 ask your telco, they will tell you what number they will use for that 800 when they direct the calls to you, many times it won't even be a DID as you're thinking