Wikipedia's article on Richard Dawkins contains this paragraph :

Oxford theologian Alister McGrath (author of The Dawkins Delusion) maintains that Dawkins is "ignorant" of Christian theology, and therefore unable to engage religion and faith intelligently. In reply, Dawkins asks "do you have to read up on leprechology before disbelieving in leprechauns?",

I would answer "no, one does not". A person does not have to read up on leprechology before disbelieving in leprechauns.

However, it seems to me that if one wants to engage "leprechists" (or whatever believers in leprechauns might be called) in intelligent debate, one needs to be at least as familiar with leprechology as the leprechist - which might mean reading a paragraph or two on wikipedia, or might require serious study of leprechology - depending on the individuals one wishes to "engage" with.

Therefore Richard Dawkin commits a logical fallacy in his rebuttal. Sure, he need not be familiar with Christian theology in order to disbelieve it. However, the "accusation" leveled by Alister McGrath was not that Richard Dawkins is ignorant of theology therefore must believe Christianity - that would be ridiculous. Rather, the theologian says Dawkins is unable to "engage religion and faith intelligently" - which would certainly be true of someone unfamiliar with the intricacies of any particular faith or religious belief system.

It seems to me that McGrath's logic is correct (whether his premises are correct or not), and Dawkins has not adequately rebutted either the logic, premise or conclusion of McGrath's statement.