Google Map rendering bug when not displayed by default

I'm not sure if this is a bug with the Google Maps renders or if I'm
just doing something wrong. I am using the "livepipe ui control
tabs": to display different pieces of data on
a page, no AJAX here, just some simple javascript events (for the
purposes of this problem, I've had the same problems when not using the
livepipe ui library.

If I display the map by default, then it renders perfectly. However, if
I display something else first (i.e. the map is hidden and then its
containing <div> is made visible via javascript) the map doesn't render
correctly. Specifically, it's like the bottom, right, and bottom right
portions of the map are grey. And if you drag it around, the rendering
never becomes normal. Has anyone else experienced anything like this?
I've attached a screen shot of the problem. Thanks in advance.