animating custom faces: in search of "open_mouth" morphs

[vr_boyko]

how to add 'open_mouth" morphs to custom faces?

After successfully creating a custom avatar face (.vzf), I noticed that lipsynching though the command speak ('foo.wav') no longer works as in the example with biohead_talk.vzf in the Custom Avater Heads tutorial. This is due to the lack of "mouth_open' morphs in my custom faces.
So I am left with 2 burning questions:

How would I go about adding various morphs to a custom face either in 3DMeNow or in PeopleMaker?

and more importanly,

is there a general way of adding morphs to various custom faces (maybe just extracting the jaw from the .vzf and lowering it) as opposed to editing every single head?

help is much appreaciated, as I am very new to Vizard