[Zope] FreeBSD : anyone else noticed kernel "table full" errors when Zope is installed ? Zope is installed ?

[chas]

I have 4 almost identical servers : 
- FreeBSD 3.2
- MySQL
- Apache 1.3.6

All were running various websites using CGI scripts. 
All were stable and have more than sufficient resources.

I've since installed Zope on 3 of them and all 3 in question
have subsequently started throwing up the following 
kernel log messages as soon as Zope is installed (running
on the backend of Apache) :

> file: table is full
> file: table is full
> file: table is full
> file: table is full
> file: table is full

This is easily resolved by increasing the MAXUSERS in the
kernel but what worries me is that I should even need to
do this. One of the boxes was handling 2 million hits 
per day last month without creating these kernel errors.

I am tempted to assume that this is all due to Zope because 
the correlation is so strong - run Zope and these errors occur,
don't run zope and don't get any. Even for one of the servers
that is still offline with zero traffic. 

Has anyone else experienced this on FreeBSD ?
Any reason why this might be Zope-induced ?

cheers,

chas