What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED AND THE AIRCRAFT RRETURNED TO PIT DUE TO THE FKIUGHT CREW REPORTING THAT AFTER GEAR RETRACTION AIRPLANE WOULD NOT ALLOW AIRPLANE TO ACCELERATE ABOVE 220 KNOTS. ALL GEAR INDICATIONS SHOWED UP AND LOCKED, HAD A GREEN FLT L/G DOWN INDICATION ON THE UPPER ECAM DISPLAY. THE AIRCRAFT LANDED SAFELY AT PIT WITHOUT FURTHER INCIDENT. MAINTENANCE FOUND THE EE BAY VMO/MMO SWITCH UNGUARDED CAUSING SPEED RESTRICTION OPERATIONAL CHECK OF OVERSPEED WARNING VMO/MMO USING CFDS PER AMM 34-13-00-710-002-A.