Apache Throttling Itself?

[fouldragon at aol.com]

I've just set up a new (virtual-bla-bla-bla) server for a site I'm 
working on.

The test server was FC6, with Plesk 8.3 and a recent PHP and MySQL 
hacked on.

The new one is CentOS5, with CPanel 11, and a comparably recent PHP and 
MySQL included with the install.

The site generally fell into place once I fixed some incorrect 
absolute/hard coded stuff, except for one thing:

One of the scripts on the site is expected to get POUNDED (it provides 
an interface to a database, which is potentially digested by sites 
hosted on the same server and different servers)

On the test setup, it worked fine.

On the new set up, if you hit the script too frequently -- 5 or 6 times 
per second or so, the server responds "403 forbidden".  If you lay off 
for a couple seconds, it works fine again.

Since the script can be hit several times in the "back end" of 
generating a page, that's unacceptable.


The signature of the server is Apache/2.2.8 (Unix) mod_ssl/2.2.8 
OpenSSL/0.9.8e-fips-rhel5 DAV/2 mod_auth_passthrough/2.1 
mod_bwlimited/1.4 FrontPage/5.0.2.2635 PHP/5.2.6 Server at (snip) Port 
80



I suspect it's some Apache setting knocking the users off, since Apache 
claims responsibility for the 403, but can anyone give me a good place 
to start looking?  I don't want to just dump the httpd.conf from the 
other server (which is a LITTLE different configuration-wise) on here 
and hope.