My code is at
http://jsfiddle.net/user1212/G86KE/4/
The problem is in gmail it leaves an extra white space between 2 tables inside the same cell.
I have tried
display:block
worked great for the gap problem between my body and footer, but it didn't do anything for my header; neither did the other fixes. I know this is an old thread, but in case anyone stumbles across it and the above didn't help, this did it for me:
Add You might have to try a couple of different tags to find the right one, but it's another solution to try.style="line-height:1px; font-size:0.0em;"
to the tag which contains your header table.