My strange iPad incident

I had a very strange iPad incident today.  I was using my iPad to take notes while building some servers.   I have the magnetic cover for my iPad2. I had the cover flipped behind.  I put the iPad down on top of a server so I could type.   I went to pick it up and noticed it was magnetized to the server.    It was also dead.   Nothing would bring it back.  I plugged it into AC power just to see if anything happened.  About 45 minutes later, it just turned on and is fine.