Motorola V710

I you send a text message first you put the number then you goto the next screen you type your message then the next screen is a confirmation page. If you hit the menu key at this point you have "send later" as one of the things you can do. You pick a time to send your message and then it will send it to the network for send at your set time. so your phone does not need to be on for it to send.
Has anyone got "send later" to work?
my phone says it has been sent to network but it never gets delivered