setVertSelection in Mesh Select modifier?

[jeff]

I'm having trouble trying to use the setVertSelection function in a Mesh Select modifier. Trying to do so in either a scripted plugIn (extending Mesh_Select), or directly via the maxScript listener, produces the following error:

-- No ""setVertSelection"" function for Mesh_Select:Mesh Select

I know there was trouble accessing this in earlier versions of Max, but I thought I'd try it again using 2008.
The purpose is to create a scripted plugIn that extends Mesh_Select to enable selecting each "Nth" sub-object, i.e., every 5th vertex, or every 10th face, etc.

Any advice would be appreciated; alternative approaches welcome.

thanks,
jeff