Have you read AT&T implementation guide?
http://www.cisco.com/c/dam/en/us/solutions/collateral/enterprise/interoperability-portal/flexible-reach-v2-isr.pdf
Lots of other CUCM/IOS versions as well in that interoperability portal (as well as lots of other carriers):
http://www.cisco.com/c/en/us/solutions/enterprise/interoperability-portal/networking_solutions_products_genericcontent0900aecd805bd13d.html
I notice you're doing the translation on the outbound dial-peer. Although there's multiple ways to do it, I've always done the inbound call translations on the inbound dial peer, so I'm dealing with Internal Ext as soon as possible in logical call flow. This means my Outbound Dial Peers are unique for Out to PSTN and Out to CUCM; and allows for SRST mode (if used) where phones directly register to Router in CUCM outage, Router will get 'automatic ' dial peer destination (of sorts) of the phone ext, and send the translated called number directly to the phone extension.
Also check on your CUCM trunk that you have defined an inbound Calling Search Space, and it includes a partition with the extension you're targeting (225). RTMT can also help in easily monitoring what calls are coming into CUCM in real-time for what destination numbers...
Example of my typical inbound dial-peer translation:
dial-peer voice 110 voip
description ** Inbound SIP Trunk (PSTN) **
translation-profile incoming Inbound_DID
session protocol sipv2
incoming called-number ^555.......
dial-peer voice 40010 voip
description ** Outbound to Call Manager **
destination-pattern ^123..$
session protocol sipv2
session target ipv4:10.10.10.1 !CUCM IP!
voice translation-profile Inbound_DID
translate called 5
voice translation-rule 5
rule 10 /^5551234567$/ /12301/
rule 11 /^5557654321$/ /12304/
In this example case, make sure CUCM is then setup to accept inbound calling search space for ext 12301 and 12304 at a minimum.
