Domain Logon slow over Wireless Network

I manage a small network, where we use Active Directory to manage users, and access. Log on and off is fairly fast on the Wired PC's. However recently I added a laptop, and a wireless desktop to the network, and their log on is VERY SLOW, It freezes up at "applying personal settings" I believe. About 5 minutes later it will finally log on. Any advice for me? I have a feeling I need to tell my DC that the wireless network is OK to be connected through, but not sure how.

Any advice will be appreciated