For the last time, this is what is going to happen on episode 3 before the star wars logo appears: we'll see obi-wan, anakin, C3PO, R2-D2, owen and beru running towards each other, on the tatoonie desert. They'll hit each other's heads, and fall to the ground with their memories wiped out. Then GL will appear and say somtehing like "woo, that was a close one! almost forgot about that plot hole! and now for something completly different...", and the star wars logo appears.
Either that, or he'll just ignore that plot hole, and during a press conference to promote episode 3:
"Mr. Lucas, first let me congratulate you on your 6 near-perfection films that compose the amazing star wars saga."
"Thank you."
"But one question remains unanswered: why dosen't C3PO tell Luke he is the son of his creator, and why dosen't he recognizes Owen Lars?"
"F##k! Damn I knew there was something missing... Ok, George, don't panic, do NOT panic, you are in control here..!"
"Mr. Lucas, we can hear what you are saying. You are thinking out loud."
"Shut up, shut up! Ok... The thing is... this happened because of... evil sith-related ewok magic powers. And it'll all be explained on a scene I'll include on the Prequels Special Edition. Now, this press conference is over! Guards, kill'em all!!"