Using WP FRONTEND plugin among sites (A and B)

Hi guys,
I’m newbie here and It’s the first time i’m posting in wordpress forum. I’m using WPMU and a plugin called WP USER FRONTEND, which is great! I just want to know if I could do the following operation.
So, I have two sites and let’s say (A and B) Where (A) is the main one and (B) a subdomain used as a forum. Now I would like to use the plugin in (B) to post articles in (A), could it be possible to do something like that? if not is there any way you can suggest me to do that could workout to my case! Thank you for the help..