Obi-wan Kenobi... Obi-wan. Now that's a name I haven't heard in a long time... a long time.
LUKE
I think my Uncle knew him. He said he was dead...
BEN
Oh, he's not dead, not yet... not yet.
LUKE
You know him!
BEN
Of course, of course I know him, he's me! I haven't gone by the name Obi-wan since before you were born.
Yeah. About five frickin' seconds before he was born, maybe.
Sheesh.
It is incredible how much the prequels ruin the OT with things like this that should really matter, but they do.