Version: (using KDE 4.4.3) OS: Linux Installed from: Gentoo Packages kget showed error window about not writeable path, setting default path in group settings helped.
Ok, that is an issue in kdelibs, I hope to be able to commit the fix soon. One workaround is to specify the default download dir: "System Settings/About Me/Paths/Download Paths"
Fixed in r1128227 for trunk and r1128233 for 4.4 branch.