How to correctly return an array of ints from service?

edit

I have the following code:

RouteRemainder.srv:

---
int64[] route_remainder

routes_manager,py:

...    
rospy.Service( "/route_remainder", RouteRemainder, self.route_remainder_callback)
...
def route_remainder_callback(self, msg):
    return [1, 2, 3]

When I call rosservice call /route_remainder, I get:

ERROR: service [/route_remainder] responded with an error: service cannot process request: handler returned wrong number of values: Invalid number of arguments, args should be ['route_remainder'] args are(1, 2, 3)

What could be the problem?