I use ContextRouter to host a handful of different domains and I see this error message in the log from time to time:
[ContextRouter] You may have conflicting http_host definitions for the www subdomain. Overwriting context web with whateverdomain.com for host www.whateverdomain.com
I’m not aware of any specific problem related to this but I’d like to know what it means and whether it makes any difference to anything. I use web rules to redirect www to the bare domain so I’m not sure how a www-prefixed domain is even reaching MODX.