Hard sudoku

I play a bit of sudoku, usually using a great little mac widget that generates puzzles. The puzzles are usually challenging but I have never been stumped until now. Which makes this a fun puzzle to post.

		3		2
		8		4		1				7
	6							5
4								9
	5			9				3
		2		5						4
				7		3			1
					6
1						4