zd1211rw 802.11a?

I'm looking at the ZyXEL AG-225H wireless USB adapter specifically because of 802.11a. According to the website, the driver currently doesn't support "A", but I did find the patch someone created at:

http://sourceforge.net/mailarchive/message.php?msg_id=8670543.post%40talk.nabble.com

He mentions that some things don't work, and I'm wonder what this exactly entails. It'll be used in an situation where there might be 30 networks to connect, and we just need to be able to connect to ours at the 5GHz frequency. Will the patch work?