thunderbird compose email window loads in the background
 

Hopefully there's a cimple answer for this one. I'm using Thunderbird 1.5 beta, and have my Preferred Applications in Ubuntu configured to run '/opt/thunderbird/thunderbird %s' when I click on mail links. The window comes up, but in the background. Is there something I can change or add to preferences or about:config? Or a command-line option?

Thanks,
Ethan