samba - Oct 2004 - skel_opaque.so, skel_transparent.so, readonly.so, default_quota.so, expand_msdfs.so, examples?

Hi sambatistas out there,
i am looking for examples and descriptions
for this vfs modules
skel_opaque.so,skel_transparent.so,readonly.so,default_quota.so,expand_msdfs.so
does anybody of you use them in production systems ?
Best Regards