Hi Peter ... I found the likely answer to this on another forum last night -
http://forums.whirlpool.net.au/forum...fm/365349.html - basically a combination of a firmware problem and Safari being very intolerant of it. I then tried accessing the router via (shock horror) IE for Mac which I still have installed. And it crashed the router! So I think we can now discount FF 3.0.9 as the problem.
Next theory - does this just mean the router is dying? Why would trying to access the admin pages on it cause it to crash?