Can we have store-and-forward SMS please?

So I'm on the tube this morning and realise I need to tell Holly something. I send her atext message on my phone. Now this is pretty damn advanced phone, you'd think it could handle that. There is, of course, no mobile reception on the tube, but it should be trivial for the phone to wait until there is reception and then send the message. Don't fucking expect it!

So when can we expect store-and-forward to work for SMS? We're not talking rocket science here.