[Zope] HTTP_ACCEPT

Greetings Zope Fans, There is a value included in "REQUEST" called HTTP_ACCEPT. Is there a way within Zope to reset this value? The default seems to be "*/*", but our sysadmin says Zope would get along better if we can change it to include the alias that Zope has been assigned by our Proxy Server. Thanks! Jery S.