Could a Thread.Sleep never return?

I have a problem with a Thread.Sleep() thats never returns, it doesn’t happens always but most of the time.
Is this possible?

There are three threads runing at the same time with all normal pririty.
The sleep is 100ms and it’s inside one of the three threads., G120HDR

There was a bug that could cause this but we have it resolved. I am thinking this bug is still there! Anyway you can provide us with a sample we can use to reproduce this?