[horde] Enabling memcache causes white screen of death

[a.smith at ukgrid.net]

Hi,

   just wondered if anyone on the list knows why this might be  
happening. I have the following system:

FreeBSD 8.0-p2
apache-2.2.15_9
php 5.2.13
horde-base-3.3.8
horde-imp-4.3.7,1
horde-turba-2.3.4
memcached-1.4.4_2
pecl-memcache-3.0.4


When I try and enable memcache in horde (via the web admin) and then  
logout, I get a blank white screen. If I check the horde log there is  
nothing written, in the apache error log I have:

[Tue Jun 08 01:16:00 2010] [notice] child pid 93310 exit signal  
Segmentation fault (11)

 From the horde test page it states "memcached Support (memcache): Yes".
I found this simple test for memcache on another site:

<?php
$memcache = new Memcache;
$memcache->connect('localhost', 11211) or die ('Can\'t connect!');
$version = $memcache->getVersion();
echo 'Server version: '.$version;

This successfully returns the version of the memcached daemon.
After that Im not sure what else to do, Ive not previously used  
memcache so may be missing some basic tests...

thanks for any suggestions, Andy.