[Zope] Connection reset by peer - ZServer problem ?

Using just ZServer (not apache/pcgi), I've been getting intermittent "Connection reset by peer" errors. The annoying thing is that sometimes it happens, sometimes it doesn't. But it only occurs when submitting forms. I remember running Netscape webservers a few years back, we would get the same problem (which was solved when I moved to Apache). Is there some way to get ZServer to stop doing this or must I use the Apache/Zope mix instead ? Thank you, chas