Which version are you using? I'm using 0.5.99 from the site below, and I only experienced that message once while trying it a few minutes ago. Now it just freezes up. :-/ Maybe this will be fixed before 0.6.0.
deb http://www.evane.org/debian/experimental ./ - Experimental Debs
BTW, I too am on Debian Sid w/ Gnome 2.4.x