I've found that This error appears when xfce4-clipman-plugin. If you close or kill this application, Inkscape does not complain.
I think the problem is not Inkscape, but clipman plugin in this case. It also makes mousepad fail to Find & Replace properly: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=612005 So it's something to inform the XFCE Team. Cheers. -- Marco
