[TomKatt]

Ok I have battled this for a little while and have found what appears to be the answer. The connection problem with my linksys router and leopard 10.5.2 is a simple fix. I had to update the router firmware from liksys. This seems to have solved the problem with leopard and had no impact on any of the other wireless items I use. This may be a problem you run into if you take your Macbook to another location (hot spot) where they have not updated their firmware. Or you could buy a new router with more up to date firmware. A lot like getting a new windows system and having to update the drivers for things like cameras printers etc.. I think this is the right fix and not a work around. Apple Care suggested this fix.