Unable to reboot/shutdown using webkit greeter

[zensubz]

Hi,
I use MDM as the default display-manager in Debian (testing with MATE) using sysvinit. I have observed a strange issue with the mdm-webkit greeter. I am unable to reboot or shutdown (once I logout from the user-session) and it just hangs. All I do in that case is go to a tty and then reboot/shutdown. I have observed the following output while it completes reboot/shutdown process:

I do not observe this issue with the mdmgreeter (with the GDM themes), but the moment I switch to webkit greeter (with any HTML themes) the problem returns. I really like the animated login screens that the HTML themes present, so would like to know if this reboot/shutdown problem could be resolved.

Thanks.