[PHP-INSTALL] mod_php_memory_usage not working

[Eric]

OK, I've recompiled php 5.0.3 on my 3 web servers with --enable-memory-limit, 
however using the %{mod_php_memory_usage}n for the LogFormat directive in the 
apache config still doesn't work.  All it reports to the log file is 0 for ever 
php script that gets ran (reported a '-' before i recompiled php with 
memory_limit support).  It's the same on all 3 of my servers.  The LogFormat 
directive I have looks like this:

LogFormat "%h %l %u %t \"%r\" %>s %b PHP:%{mod_php_memory_usage}n 
\"%{Referer}i\" \"%{User-Agent}i\"" memoryusage

memory_get_usage() works fine and any process using up too much memory gets 
killed successfully, so I know support is definitely compiled in.

Thanks,
 Eric