I am a female, and I can't multitask, at all.
I need to give all my energy and focus to whatever is immediately facing me. If I'm in a situation where multitasking is required, I get really flustered and stressed. Needless to say, my job as a server didn't last long!
I have never noticed a gender correlation to multitasking abilities. It's more of an individual issue, as are most things that people try to assign to gender.