minecraft "damaged and can't be opened"
I downloaded the Mac 1.4.6 version of Minecraft to the 2012 iMac but I keep getting the "Minecraft is damaged and can't be opened. You should move it to the Trash" message. I downloaded the same app to a Retina MacBook Pro and Mac Pro -- both running 10.8.2 Mountain Lion and it launches and runs fine on those two Macs.
Any ideas?
One of everything Apple makes, Mac OS X (10.7.1)