WEP Encryption Q's

So we just got a new router today, and it works great. There's one thing that I'm still having trouble with though. We have a 802.11b/g mixed network, and whenever I try to setup a WEP encryption, it works fine on the b device (an old laptop with XP on it), but when I try to connect with the g device (MacBook), it says there was an error connecting. I have no clue as to why this is happening. We need some kind of security besides MAC filtering, and WEP seems like the only good one since WPA is so easy to get past.

Again, any help at all is appreciated. Thanks.

[Oscar]

push the white / yellow flashing button on it? I have the same one and mine sometimes throws a fit and I hit that button and works fine. If all else fails, reset it!