spiral - 8:05 pm on Jan 31, 2006 (gmt 0)

From my experience the best and easiest way to avoid problems is to stick to one version (with or without www, it does not matter) and make general 301 redirection from one domain to another.
If you like your site with www, then redirection should be for all URLs without www to the same pages with www.
It can we made by configuring your web server or by server side include file - both depending on your web server type.