Definitely very weird... not seeing anything in base or optimistic that could cause this to screw up. I would say that maybe there's a plugin overriding that method somewhere, but you would think that would show up in the stack trace then.
Well, first, for a sanity check, create a new project and just make a simple table and model. See if you get the error there. I doubt you will or someone else would have complained about this (not finding anything in the rails trac). Also, try grepping through the entire project for anything that might redefine attributes_with_quotes.
Ultimately, if you can't sort it out, I would open a bug and roll back to a previous revision.
b