"Wet dream"

In an e-mail group for Swedish translators, we have come to discuss the phrase "wet dream". Some of us feel that only men can have a wet dream, others that this is pure nonsense... Interesting, right?
This is the definition from Merriam-Webster Online:

"wet dream
Function: noun
Date: 1851

an erotic dream culminating in orgasm and in the male accompanied by seminal emission"

What do =you= say - must a wet dream be "accompanied by seminal emission"? Can both sexes have it? Does the phrase emanate from the involontary "wet dreams" that adolescent boys have?

Taking this question solely upon its etymological merits, Merriam-Webster Online clearly infers in its definition that a "wet dream" can be had by either sex. Personally speaking, it'd not have occurred to me to use the phrase to refer to an erotic dream had by a female, but then again, one can see that a case could be made for it.

Perhaps those of a feminine persuasion can shed a more relevant light here?

If you don't know, we ain't telling.