Normally not, except for some mtu issue, with which normally you could adjust anyway on some VPN clients
it should work fine. Also, make sure you use the latest drivers for wireless NIC you are using. If you are talking about Wireless Lan, the Cisco VPN client to VPN concentrator with the Cisco Aironet cards and AP works fine. If you are talking about wireless network that some ISP offer and you would be
using it with a PDA or such, Certicom has partnered with Cisco for their Movian client to be able to connect via VPN to a VPN 3000 concentrator.
