Possibly you detached from world community grid when it got correctly attached, but in the project tab you left http://www.communitygrid.org which is giving these messages. When replicating what you did on my machine, got

3267 http://www.communitygrid.org/ 11/19/2014 12:00:07 AM sched RPC pending: Project initialization
3268 http://www.communitygrid.org/ 11/19/2014 12:00:07 AM [sched_op] Starting scheduler request
3269 http://www.communitygrid.org/ 11/19/2014 12:00:07 AM [sched_op] Fetching master file
3271 http://www.communitygrid.org/ 11/19/2014 12:00:10 AM [sched_op] Got master file; parsing
3272 http://www.communitygrid.org/ 11/19/2014 12:00:10 AM [sched_op] Found 0 scheduler URLs in master file
3273 http://www.communitygrid.org/ 11/19/2014 12:00:10 AM [error] No scheduler URLs found in master file
3274 http://www.communitygrid.org/ 11/19/2014 12:00:10 AM [sched_op] Deferring communication for 00:01:32
3275 http://www.communitygrid.org/ 11/19/2014 12:00:10 AM [sched_op] Reason: Couldn't parse scheduler list

It's interesting for it to be possible to attach to anything, real or imaginary. Someone could set up a honeypot with how things seem to operate, a bogus project and wait for more like in this case attach typing the wrong url and then start computing whatever.

Almost great, please confirm you've obliterated the connection with the faulty www.communitygrid.org site by selecting it in the project tab and hitting the remove button on left side. This will ensure you get rid of the false and stumping messages and nullifies the chance of there ever anything being send from that address to your agent.

Best practice is to only add projects that come off the dropdown list in the manager. Those are the berkeley recognised sites, their project master table updated whenever there is an update. The agent is supposed to take care of this.