The intent of the prohibition is to prevent exactly your use case, albeit more geared for people that want to sell their old plans instead of giving the away. It's meant to intentionally make that inconvenient for you by making you give up your number.
Originally Posted by georgethegreek
Make things easy on your family and move them to a carrier that is as anal. Not a positive trait in people nor in carriers.
Unlocked Pentaband iPhone 5 (AWS), unlocked iPhone 4
Unlimited airtime, Unlimited CAN/US long distance, Unlimited SMS to CAN/US wireless numbers
2500 Call Forwarding minutes to CAN/US numbers
Google Voice for visual voice mail with message transcription, conditional greetings, unlimited messages (vs 35 message cap), remote retrieval from any PC or phone, no auto-purge after 10 days and most importantly no $7-$8 charge.