Open a local file from an AIR application

Hello people, I just have one question.

I’m currently developing a download manager, in which the user can download several zip files from a website. I’m able to stream down those files, save them to the local file system, and check if they already exist. My question is, how can I open one of these zip files from the AIR app… just like if you’d double clicked on the icon from the Finder on a Mac or Windows Explorer on a PC?

Thanks for your help.