Ah. This is the difference between using native drivers and using ndiswrapper.
ndiswrapper is a hack to let Linux use Windows drivers. It works, but only for small values of work.
If you want full support, like WPA, you need to use a card that uses native drivers.
ndiswrapper doesn't support encryption on every card that it "supports."
I posted a thread on the Mint forum.
http://www.linuxmint.com/forum/viewtopic.php?f=53&t=14222&p=88033#p
Take a look and tell me what you think.
Ray