A-whiling a-way some a-time

Tell me something. The word "awhile" is correctly used in this sentence:

"I want to sleep awhile."

but wrongly used in this sentence:

"I want to sleep for awhile."

- right? Because in the second sentence you'd use "a while", which is two separate words.

Dictionary.com says:

Usage Note: Awhile, an adverb, is never preceded by a preposition such as for, but the two-word form a while may be preceded by a preposition. In writing, each of the following is acceptable: stay awhile; stay for a while; stay a while (but not stay for awhile).

But I've been coming across the second-sentence-type usage more and more often lately, so I'm beginning to think that maybe it's becoming acceptable usage - or perhaps it always was in the US? (It's always been American writers using the word in that way.)

ETA: Mirriam-Webster Online says:

Usage: Although considered a solecism by many commentators, awhile, like several other adverbs of time and place, is often used as the object of a preposition .

Oh, crap. I still think "for awhile" is wrong.

Call me an impossible purist*, but I hate it when this happens. I'm all for the elasticity of the English language, but the line between growth and mutilation is quite thick, thank you very much.

Same bloody thing happened to "enormity", which used to mean "wickedness" but with perpetual misuse has now come to mean "bigness", too - so that often, I can't tell which meaning of the word the author intends.

And nobody else seems to care about this. Sometimes I feel like I'm the only one trying to plug all the leaks in the language.

[/rant]

*The other day I was looking for Eminem's "Lose Yourself" on Limewire. I could see a file up there with the highest number of sources (66)... but the file was called "Loose Yourself". I didn't download it. The actual words going through my head were: I don't need that song badly enough to take it from people who can't be bothered to spell it right.