Did you try creating the scheduled task with PS (like I showed inRe: scheduling_powershell script_task scheduler )?
You can run that on the remote station through Invoke-VMScript.
The user/password can be changed on the Register-ScheduledTask cmdlet.Blog: http://lucd.info | Twitter: @LucD22 | PowerCLI Reference co-author: http://tinyurl.com/hkn4glz
i have not tested that, i have a gpo that create the schedule task during startup but that is not really neccesarry.
I will try you solution, thanks