I have wireless set up throughout the house and have no problem connecting laptops and friends laptops.

I have security enabled as WPA with a password.

When my cousin tries to use his PDA, he can't connect.

If I disable security he can connect, but I don't really want the whole neighbourhood sharing my wireless connection.

He can connect it in other locations, for examples cafes where they have wireless and use a password.

Anyone know why this might be.

We have messed around changing the options but doesn't work unless you disable security entirely.

Puzzled

Have you tried it with WEP?

What model of phone is it? Google the model number for the manual and check the specs.

Are you sure the phone supports WPA, if so does it support WPA or WPA2? If the phone is wi-fi certified, and came out after 2006 - it has to support WPA2.

Have seen issues where phones/PDAs only support limited PSK length (something to do with the hashing function used to calculate the hex values), try changing the PSK to length 8. (think that's the minimum.)

Either way the above suggestions will compromise the security of your network.

One solution would be to have another SSID on a different (V)LAN seg. and restrict/shape the traffic. I guess thats a bit over the top for home use though.

Another solution more appropraite to home use would be to have a differnet SSID and use MAC authentication, that way only he can use the net.

<rant on>

Generally you should not use WPA in PSK mode as it is inevitable that users will choose weak passwords. To be honest I hate Wi-fi for this very reason, you spend ages setting up topology/policies and somebody comes along and brute forces the net.

With another encription/handshake scheme coming out - wifi simple connect - things are only going to get worse.

</rant on>