How do you customize text message reply?

[generic username]

One of the coolest features in GB is text message reply, which allows you to send a text to a caller when you select ignore call, a la Palm phones. The feature includes the following pre-set selections shown on the pic below:

I have read in a few places that the feature allows you to cusomize the list of texts that you can use with the feature. My question is, HOW do you customize the list? Thanks in advance.

 

[pool_shark]

Check the radio button for create new message.