This fix will automatically apply to all background images as well as in img tags:
SuperSleight adds a number of new and useful features that have come from the day-to-day needs of working with PNGs.
* Works with both inline and background images, replacing the need for both sleight and bgsleight
* Will automatically apply position: relative to links and form fields if they don’t already have position set. (Can be disabled.)
* Can be run on the entire document, or just a selected part where you know the PNGs are. This is better for performance.
* Detects background images set to no-repeat and sets the scaleMode to crop rather than scale.
<!--[if lte IE 6]>
Download : http://24ways.org/code/supersleight-transparent-png-in-ie6/supersleight.zip