Quite likely your http_access rules blocks the digest exchanges. Or you are running an early 2.6 version where internal requests did not work in accelerator mode.
which http_access rules can block digest exchanges? Can you give me an example? I'm running CVS as of this friday. Also, I see this at the end of my cache.log file: icmpSend: send: (111) Connection refused 2006/10/01 13:05:55| Closing Pinger socket on FD 115 Thanks.