Cracking Windows Passwords in Ubuntu using ophcrack

I really can't believe what happened :S :S :S, I just downloaded a software called" ophcrack" within my Ubuntu installation, and it could - in less than a minute - find out the password I use for my administrator account on my Windows XP installation on the same machine!!!!
I'm totally paralyzed :S :S :S

To install this software, type "sudo apt-get install ophcrack" and then download the necessary tables to be order to crack the password from SourceForge, load the tables (There are many other tables than the one I'm using, there are even some commercial ones) & have fun :)))) (Don't forget to read the manual, it's very useful)