This is set on the line appearance of the the Remote Destination Profile. The last section of the DN configuration will have four check boxes which specify what Caller ID information is forwarded. (Sorry, I don't remember the name of the section at the moment.)
The caveat here is that your provider must allow you to set ANI information for an outbound call to a number that you don't own (the original caller). Some providers won't do this and override the ANI with your company's main billing number when the ANI is wrong. If the settings in UCM are correct, you may want to check with your provider.
