Monitoring a Tru64 Server with netsaint_statd

Hello,
I have problems to monitoring Tru64 with netsaint_statd, when i try to use check_disk.pl.
This is my df -k output of the server that i try to monitoring
bash-2.04$ df -k
Filesystem           1k-blocks      Used Available Use% Mounted on
root_domain#root        524288    109770    401544  21% /
usr_domain#usr         9824504   2577217   7208296  26% /usr
var_domain#var         1046280    370708    669104  36% /var
tmp_domain#tmp        17782536    161134  17613576   1% /cluster/members/member0/tmp
spe253:/house        159976688 123788318  35125088  78% /house
i_domain#i      11587088    285477  11292224   2% /i
and when use:
 check_disk.pl 192.233.54.167 usr_domain#usr 80 90 
i got this message:
"Disk usr_domain#usr not mounted or nonexistant"
but just working fine whe i try to see spe253:/house :
check_disk.pl 192.233.54.167 spe253:/house 80 90
what is wrong, i can´t understand what is the problem, could you help me?.
Thanks in advance.