Removing proxy requests from Access Log

I am running a single httpd daemon that acts as a proxy server as well as serving local documents. Is it possible not to have proxy requests logged in the access log?

Monica Berko                                     Email:Monica.Berko@anu.edu.au
Centre for Networked Information and Publishing  Phone: (06) 279 8114
Australian National University                   Fax:   (06) 279 8120