OS X :: No Option To Keep Window Below Dock In 10.6?

This is a bit of a strange problem, and I'm not entirely certain what caused the behavior I liked in the first place. I thought it was a Snow Leopard problem, but friends of mine have said they've never had the behavior I seem to have lost. I use Adium every day, and I like to have my window in the bottom corner of my screen, below the top of the dock, like so: In Leopard, this window always stayed in its position, even if I closed it.

However, after upgrading to Snow Leopard, the bottom of the window aligns itself to the top of the dock. This is an irritating behavior and I'd like the old one back, however, I've done some pretty extensive searching to no avail. In lieu of getting this exact behavior back, could anyone recommend a program that might force the window to remember its old position or lock positions or something?