Apache::Session::MySQL, light/heavy proxy, wedging

[Todd Finney <suppressed>]

I'm having a problem with Apache::Session::MySQL and mod_proxy, and I can't 
seem to wrap my head around what's going on.

I have two servers running in the light/heavy configuration as outlined in 
the guide.   Both servers are 1.3.34.  On the lightweight server, my proxy 
section looks like this:

----
RewriteEngine on
RewriteRule ^/images - [L]
RewriteRule .(css|ico)$ - [L]
RewriteRule .swf$ - [L]
RewriteRule ^.(.*) http://192.168.0.4:8080/$1 [P]
----

On the heavy server, I'm running ePerl with a PerlHeaderParserHandler that 
is essentially just a wrapper for Apache::Session::MySQL

----
PerlHeaderParserHandler BoyGenius::AccessManagement::SessionTestTwo

<FilesMatch "\.phtml$">
       SetHandler perl-script
       PerlHandler Apache::ePerl
</FilesMatch>
-----

I have a big complicated handler that does all kinds of fancy crap, but in 
the interest of nailing down the problem I've replaced it with one that was 
pretty much cut and pasted from the Apache::Session perldoc:

----
package BoyGenius::AccessManagement::SessionTestTwo;

use Apache::Session::MySQL;
use Apache;

use strict;

sub handler {
    my $r = shift;

    #read in the cookie if this is an old session
    my $cookie = $r->header_in('Cookie');
    $cookie =~ s/SESSION_ID=(\w*)/$1/;

    #create a session object based on the cookie we got from the browser,
    #or a new session if we got no cookie

    my %session;
    tie %session, 'Apache::Session::MySQL', $cookie, {
        DataSource => 'dbi:mysql:boygenius', #these arguments are
        UserName   => 'nobody',         #required when using
        Password   => 'XXXXXXXXX',           #MySQL.pm
        LockDataSource => 'dbi:mysql:boygenius',
        LockUserName   => 'nobody',
        LockPassword   => 'XXXXXXXXX'
        };

    $r->pnotes('SESSION_ID', $session{_session_id});

    #Might be a new session, so lets give them their cookie back
    my $session_cookie = "SESSION_ID=$session{_session_id};";
    $r->header_out("Set-Cookie" => $session_cookie);
}

1;
----

The problem I'm having is with this line:

    $r->pnotes('SESSION_ID', $session{_session_id});

When this line is in there, I see the following behavior:

- When I fire up a new browser and access http://192.168.0.4/, the browser 
hangs.  In my bigger fancier handler with more detailed logging, it seems 
to hang right before the session tie.

- When I fire up a new browser and access http://192.168.0.4/index.phtml, 
the page comes up as it should.

- When I fire up a new browser and access http://192.168.0.4:8080/, the 
page comes up as it should.

- When I fire up a new browser and access either 
http://192.168.0.4/index.phtml or http://192.168.0.4:8080/, and then access 
http://192.169.0.4/, the page comes up fine.

- When I fire up a new browser and access http://192.168.0.4/ and then 
access either http://192.168.0.4/index.phtml or http://192.168.0.4:8080/, 
none of the pages will come up.

I've replicated this on two different setups, and it acts the same everywhere.

index.phtml has nothing but straight html in it, if that matters.

I'm not even going to attempt to guess what's going on here, but I could 
really use a smack with the clue brick.

thanks!