How to put individual column filter inputs at top of columns?

I've tried to modify the column filter using text box inputs example to move the inputs to the top of the columns as seen here, http://jsfiddle.net/s8F9V/.

It works, but, the inputs now also trigger the column sorting when I click in them. The column header text no longer triggers the sort.

How can I have it such that the column header text triggers the sorting and have the text box input filter the content?