Why not set them a test of coding something, using your environment.
See how the code looks - and quiz them about their approach, logic and reasoning.
I for one have no idea how the Zend architecture works! I also couldn't tell you what the regular expression to split an email address is, in PHP or not...
I dont see them as rememberable - sure if I need to know, I can find them out - because as a professional web dev - thats what I do - I problem solve!