m1l-suse:/var/log/cups # less access_log
localhost - - [08/Jan/2010:21:54:06 -0600] "POST /printers/MFC7840W HTTP/1.1" 200 372 Create-Job successful-ok
localhost - - [08/Jan/2010:21:54:06 -0600] "POST /printers/MFC7840W HTTP/1.1" 200 784 Send-Document client-error-document-format-not-supported
localhost - - [08/Jan/2010:21:54:06 -0600] "POST /jobs/ HTTP/1.1" 200 169 Cancel-Job successful-ok
m1l-suse:/var/log/cups # less error_log
E [08/Jan/2010:21:54:06 -0600] Returning IPP client-error-document-format-not-supported for Send-Document (ipp://localhost:631/printers/MFC7840W) from localhost