JESS: slot comparison

hi fellows,
i am new at jess. i am using it in combination with protege (jessTab).

my problem is that i want to compare the value of a slot with a specific
value.
----------------------------------------------------------
(defrule SlotWithLessValueThan
?obj <- (object (is-a Data)
(idNikos > 65000.0))
=>
(printout t (instance-name ?obj) crlf)
)
----------------------------------------------------------

when i hit (run), the rule fires but it doesnt work because i have at least
three instances with slot-values greater than 65000.0

p.s. the slot has a range float.

thx for your answers