Problem with floated images in the main content area

With zen-fixed 5.x-0.6 if I put something like the following in my main content area, there is no padding between the image and the text. E.g. instead of floating right with a little bit of breathing room on the left, the image winds up smushed right up against the text. Even weirder, if the main content area has local task tabs then initially the left hand padding appears correctly, but then when you wave the cursor over the local task tabs the image suddenly jumps to the left!

Here is example problematic content:
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This is some text. This is some text. This is some text. This is some text. This is some text. This is some text.

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The problem seems go away if I modify the #squeeze element in layout.css and comment out "position:relative".

I don't see any ill effects with this modification. You can check out my drupal site here, maybe there is some subtle problem with it now that I haven't noticed?

What is the "position:relative" supposed to do?