We have the Fundy Software Inc. facebook page integrated with Zendesk, so we will often see private messages (these say reply via page message) and wall posts (these say reply via wall).

• For private/page messages, we can give general info about the software, but if a user is requesting help for a software or billing issue, we ask them to submit a ticket to fundy.com/support.
• For wall and page posts, we use a standard "Hi____, for help with software or account related questions, please submit a ticket to Fundy.com/support. We'll be happy to help you there!"
• For both private messages and wall posts, we mark them as solved rather than pending, even if you're waiting for a response 
• If we get an add for Fundy via private/wall post from Facebook, just delete