[wp-hackers] the_post_thumbnail 'full' with no width/height attr

[Kevin Newman]

Hello,

I'm trying to use 'the_post_thumbnail' to output the full size image 
(the original size not resized by wordpress), but without outputting the 
width and height (I'd like them width="100%" height="" actually, but 
empty would be good enough).

Is there anyway to do that with this function, or will I have to build 
my image tag manually?

Kevin N.