Skitch "hide on login/startup" preference does not work

No matter how many times I try and set my preferences the Skitch App does not retain the preference "Hide Skitch on login/startup". I'd like to have skitch launch on startup but be hidden.

It's just annoying to always have that window up when I start up. After setting the preference, I hit "done" and it never keeps my change.

I'm not running snow leopard. This has been happening for several months now.

Any help would be greatly appreciated.