Because of how the Blackberry gets data through RIM's network. Based on the IP your requesting the data from you appear to be in Waterloo, Ontario Canada. Not a thing u can do really.
Posted from my CrackBerry at wapforums.crackberry.com
You can only use it really if you are in range of a Wi-Fi network.
As has been said, the way a Blackberry routes it's data will mean the iPlayer app will always think you are outside of the UK unless you are using an active Wi-Fi connection.
Posted from my CrackBerry at wapforums.crackberry.com