@Override
    public void deleteProperty( String username, String propName ) throws UnsupportedOperationException
    {
        // all providers are read-only
        if (isReadOnly()) {
            throw new UnsupportedOperationException();
        }

        for (final UserPropertyProvider provider : getUserPropertyProviders())
        {
            if ( provider.isReadOnly() ) {
                continue;
            }

            try {
                provider.deleteProperty(username, propName);
            }
            catch (UserNotFoundException e) {
                // User not in this provider. Try other providers;
            }
        }
    }
Removes a property from all non-read-only providers.

@param username The identifier of the user (cannot be null or empty).
@param propName The property name (cannot be null or empty).
xmppserver/src/main/java/org/jivesoftware/openfire/user/property/UserPropertyMultiProvider.java