I guess everything is in the title... I filed this under Thunar, as Thunar Wallpaper plugin is part of the thunar source package now.
Created attachment 2271 Possible fix, puts quotes around the filename. Could you test this patch?
Created attachment 2275 add quotes around filename (%s)
Forgot the comments, the attachment also fixes bug #5057
Created attachment 2276 fixes Same patch, with another fix that checks for gconftool-2 instead of gconftool. Looking for gconftool is unsafe as it doesn't get build anymore with this name out of the source tree.
I just tested Mike's patch, it fixes the issue for me. Thanks Mike!
*** Bug 5186 has been marked as a duplicate of this bug. ***
committed, though I think this does not solve the problem when the filename contains quotes... should be fixed in next release.
Created attachment 3310 Use g_shell_quote to quote the filename This seems to work for all kinds of file names: normal, accents, quotes, spaces...
Patch pushed to git master.