Commenting function does not work

Hello people here,

Hopefully someone here can help me. Nagios here works, but the commenting function does not work.
I do get [1292594133] EXTERNAL COMMAND: ADD_HOST_COMMENT;145.58.19.243;1;stachanov;this check will only work on mondayin the nagios log.
And the permissions on the nagios.cmd pipe are good I think,prw-rw---- 1 nagios www-data 0 2010-12-17 13:00
This is on ubuntu hardy heron, 8.04. Does anyone have an idea where I should look?

for anyone else having this problem adding Options ExecCGI did the trick.