[Zope] access cvsweb thru Zope

Hi, I'm trying to find a way to use perl cvsweb CGI script via Zope. The main reason for this - use powerful auth means that Zope has. Our CVS repository is partitioned on project basis using standard UNIX mechanism (owner/group/perm). So I can't simply run cvsweb from anonymous user --- it won't has required permissions. I (probably) need to auth user first (thru Zope) and then run cvsweb.cgi from that user. Does anyone do something similar? Is it possible at all? AFAIU I should grok External Method first. -- Rgrds, Max Ischenko