I know this is an old post, but it only locks it for 5 minutes. Type into cmd ClearLock.exe /config to check it out.

While i also find this useful, there is an easy bypass. just use your touch screen to open the task view switcher, make a new desktop and then there you go. you can also use tskill and view the locked screen if you are a bit mischievous. (You might find it difficult to get the space key, as you have to copy it)