I would imagine that the wheels were made to Airbus specification, but Airbus would not design them or contstruct them.
i.e. Airbus says "we want a wheel combo to go on here, and be able to do this, and weigh no more than this amount"
The wheel then failed to meet the specification laid out by Airbus.
On the other hand the problem was obviously fixed, as the 340-600 is flying today, and wouldn't have if it could not pass the tests.