Small dbvm fix

There is a small bug in dbvm where the following code in usermode apps can completely freeze DBVM:

mov ax,ss

mov ss,ax

int1

The version of DBVM in this post fixes that issue, so people that encountered this issue can now continue using DBVM

Also, letting you know i'm still working on CE and next version is starting to look good

And remember, give suggestions and bug reports when you encounter them so I can fix and improve CE