IIS excessive logging

Trying to determine what these log entries are, and how to stop them. We are getting around 22MB/day of the exact same log entries in the IIS logs on our SCE 2007 SP1 server.

 

#Software: Microsoft Internet Information Services 6.0
#Version: 1.0
#Date: 2010-09-08 00:00:04
#Fields: date time s-sitename s-ip cs-method cs-uri-stem cs-uri-query s-port cs-username c-ip cs(User-Agent) sc-status sc-substatus sc-win32-status
2010-09-08 00:00:04 W3SVC1 10.0.0.103 POST /ReportServer$SCE/ReportService2005.asmx - 80 - 10.0.0.103 Mozilla/4.0+(compatible;+MSIE+6.0;+MS+Web+Services+Client+Protocol+2.0.50727.3607) 401 2 2148074254
2010-09-08 00:00:04 W3SVC1 10.0.0.103 POST /ReportServer$SCE/ReportService2005.asmx - 80 - 10.0.0.103 Mozilla/4.0+(compatible;+MSIE+6.0;+MS+Web+Services+Client+Protocol+2.0.50727.3607) 401 1 0
2010-09-08 00:00:04 W3SVC1 10.0.0.103 POST /ReportServer$SCE/ReportService2005.asmx - 80 RFTECH\TrackIt 10.0.0.103 Mozilla/4.0+(compatible;+MSIE+6.0;+MS+Web+Services+Client+Protocol+2.0.50727.3607) 200 0 0
2010-09-08 00:00:04 W3SVC1 10.0.0.103 POST /ReportServer$SCE/ReportService2005.asmx - 80 - 10.0.0.103 Mozilla/4.0+(compatible;+MSIE+6.0;+MS+Web+Services+Client+Protocol+2.0.50727.3607) 401 2 2148074254
2010-09-08 00:00:04 W3SVC1 10.0.0.103 POST /ReportServer$SCE/ReportService2005.asmx - 80 - 10.0.0.103 Mozilla/4.0+(compatible;+MSIE+6.0;+MS+Web+Services+Client+Protocol+2.0.50727.3607) 401 1 0
2010-09-08 00:00:04 W3SVC1 10.0.0.103 POST /ReportServer$SCE/ReportService2005.asmx - 80 RFTECH\TrackIt 10.0.0.103 Mozilla/4.0+(compatible;+MSIE+6.0;+MS+Web+Services+Client+Protocol+2.0.50727.3607) 200 0 0
2010-09-08 00:00:04 W3SVC1 10.0.0.103 POST /ReportServer$SCE/ReportService2005.asmx - 80 - 10.0.0.103 Mozilla/4.0+(compatible;+MSIE+6.0;+MS+Web+Services+Client+Protocol+2.0.50727.3607) 401 2 2148074254
2010-09-08 00:00:04 W3SVC1 10.0.0.103 POST /ReportServer$SCE/ReportService2005.asmx - 80 - 10.0.0.103 Mozilla/4.0+(compatible;+MSIE+6.0;