system.uptime on OS X 10.6

[rwa]

We have just installed agent 1.8.2 on OS X Server 10.6.4 for the first time, and system.uptime is showing unsupported. On the server we get:

zabbix_get -s<OS X 10.6 host> -k"system.uptime"
ZBX_NOTSUPPORTED

While the agent log (set to log level 4) shows:

 12497:20100728:162013.072 Processing request.
 12497:20100728:162013.073 Requested [system.uptime]
 12497:20100728:162013.073 Sending back [ZBX_NOTSUPPORTED]

This works fine when the agent is running on OS X 10.5.x:

zabbix_get -s<OS X 10.5 host> -k"system.uptime"
12546962

Has this worked for anyone on 10.6, or do you have suggestions for further diagnosis?

Thanks.