It does work. I've been beta-testing some clothing by AS3Design a couple of days ago. She did some injection poses for morphs and at the same time setting the number to something like 111. She got a pose file for P5&6 users changing the number for all the jcm's, too. Very neat trick... Everything's working fine in all Poser version from 4 to 6 :-)

Yesterday's the past, tomorrow's the future, but today is a gift. That's why it's called the present.