Record electric guitar via Amplitube

I have just bought Amplitube and use it to record electric guitar in Garageband. I add Amplitube as an effect via the Inter-App Audio interface and I get the guitar sound I want. However, when I record I expected to get the clean guitar sound recorded so that I after recording could change the guitar sound via the Amplitube effect but what is recorded is the guitar sound selected in Amplitube and not the raw guitar signal.

How can I have the guitar sound from Amplitube active while recording the clean guitar sound in Garageband and after recording be able to change the Amplitube effect?

//Erik