freebsd Memory Utilization--fetch vaule is alway 0

I download trail applications manager 8.0,hope monitor freebsd 4.9,all is good,but only Memory Utilization,it alway show is 0,can't show data.

i view the file HostResource.xml,find follwed:

<POLL ID="FreeBSD" protocolClass="com.adventnet.appmanager.util.CLIPerformDataCollectionIfcImpl" maxSessions="10">

<CATEGORY ID="Memory Utilization" command="export UNIX95;top -d 1 -n 2" parseAll="false" description="Percentage of Cache Memory, Buffer Memory and Total Memory.">
<ENTITY ID="Memory" applyThresholdOver="100 -(used)" threshold="Th6" storeValue="100 -(used)" storeHistory="true" units="%">
<PARSE line="2" token="2" name="used" />
</ENTITY>

</CATEGORY>

use this configure,can't read memory vaule.

I use ssh login,and on freebsd 4.9 ,export UNIX95 ,cant execute,top -d 1 -n 2 execute,the result is:
top -d 1 -n 2
last pid: 32718; load averages: 0.29, 0.48, 0.55 up 310+18:15:27 15:58:11
141 processes: 1 running, 140 sleeping

Mem: 131M Active, 3122M Inact, 322M Wired, 127M Cache, 199M Buf, 70M Free
Swap: 4096M Total, 8K Used, 4096M Free

PID USERNAME PRI NICE SIZE RES STATE C TIME WCPU CPU COMMAND
158 mysql 2 0 495M 99956K poll 0 76.2H 0.63% 0.63% mysqld
32653 popmail -1 0 1492K 924K nfsrcv 0 0:00 8.00% 0.39% pop3d

can't been used according to HostResource.xml.
my freebsd version is too old?

Have you good ideas about it?