The Mother of All Sudoku's

This is the mother of all Sudoku's, at least it is for the two of us.

This is for any experienced Sudoku lovers who are interested in a bit of a challenge. Inexperienced players need not apply.

We started doing this one while on vacation. We are both stumped at the same spot, and by cracky we cannot find the next spot. Of ourse, that next spot will probably cause the entire puzzle to be solved.

So, if there are any Sudoku fans out there who want to give this expert one a try...please, be our guest and work on it at your own leisure.

P.S.- we're looking for the logic of the next number...please leave a comment.

Col1	Col2	Col3	Col4	Col5	Col6	Col7	Col8	Col9
___	9	___	___	3	2	4	___	___
___	1	___	___	___	6	3	___	___
___	8	___	___	___	5	7	___	___
1	4	2	___	5	___	6	3	7
8	___	___	2	6	4	5	9	1
9	5	6	___	___	___	8	4	2
5	___	8	6	___	___	___	7	4
4	6	9	___	___	___	___	5	___
___	___	1	5	4	___	___	6	___