[Zope] Zope is very slow!

Hi, This is my first message to the list... I'm currently running Zope 2.1.6 + Apache 1.3.12 (with proxycache). The system is a Solaris 5.6 on a E450 with 2GB Ram and 2 X 450mhz... The Zope is running with Apache, using the ProxyCache and SiteAccess to convert all requests from port 8080 to 80. My problem is: The system is *too slowly*! Does anyone know how to optimize the Zope to run quicker? Is there anything wrong with this configuration?? Thanks a lot, Christiano Anderson