I may be reading the OP wrong, but this is done quite easily on my lcd at least. Plug tv into power outlet, switch power on. Switch on TV from its power on button. Now whilst the TV is on, switch it off by switching off the power at the power outlet. Now when you switch it on at the power outlet, the TV will turn on, at least it does on the 2 lcds and 1 plasma in my house.
So with your TV that has its own on/off switch at the back, leave that on ON, switch TV on, now turn TV off by switching off power at the power outlet. When you switch on at the power outlet TV should turn on.