Get a lot of this in the log:
2010:05:20-21:57:08 vretstorp httpproxy[11394]: id="0003" severity="info" sys="SecureWeb" sub="http" request="(nil)" function="sc_resolve_server" file="scr_scanner.c" line="356" message="DNS: cffs07.astaro.com: Name or service not known"
