Well no amount of measures of behaviour imply a capacity for meaning -- behaviour is a proxy measure of mental capacities.
However we might, as a practical matter, have a large number of proxy tests and treat a system as meaning-capable if it passes.
At some point you have to stop waving your hands and hand him the pen, though. What question can be asked that can be used to distinguish genuine human intelligence from intelligence simulated by a machine?
Searle thought he had come up with just such a question, but it turned out that he hadn't.