EFS (Encrypted File System) help!

I would like to automate the adding of user certificates to files once it is encrypted but I am struggling getting anywhere.  

Here is the scenario:

I have a program that finds certain files and uses EFS to encrypt them.  Most of these files are found on the network with multiple people having to be able to view/access them.  Once the file is encrypted, it only adds the certificate of the person that encrypted the file.  What I need is to be able to use a command line tool or some code to add the other users associated with this file.  Can this be done?  I have been looking at certutil and cipher command line tools and I don't see how to add users without going through the file properties in explorer.  The program itself is a VB6 app if that helps.  This is the last step of this project so any help would be appreciated.

PS - Is there a setting or something in the CA, Active Directory, etc that will automatically add the certificates of all individuals that have access to that file?  

Thanks in advance