calling methods from another object

Hi,
If anyone can help with the following....

I am trying to send a message from one object to another;
In my sending object I have the code;

atom_setlong(x->pparray, f);
object_method_typed(x->boundobject, gensym("tester"), 1, x->pparray, &rv);

and have also tried;

object_method_long(x->boundobject, gensym("tester"), f, &rv);

(boundobject is pointer to receiving object, f is long value).

In my receiving object I have the prototype -
void lh_trkmtx_tester(t_lh_trkmtx *x, long n);

and in main -
class_addmethod(c, (method)lh_trkmtx_tester, "tester",A_LONG, 0);

and the function -
void lh_trkmtx_tester(t_lh_trkmtx *x, long n)
{
post("message %i", n);
return ;
}

When testing I always receive the following in the max window everytime the sending method is triggered;
lh_trkmtx : doesn't understand "tester"

When I create a message box to send the message in via inlet1 all works fine.
Am I trying to do something that you cannot do, or am I missing something obvious?
I successfully use the same method to send a "set" value message to a dial object,
Any help or enlightenment on this would be greatly appreciated... I 'think',,,.. this is my last programming stumbling block!

Kind Regards,
Leigh