Internal messaging system for Magento 1.7

I would like to have an internal messaging system built into Magento 1.7. This system needs to have the ability to send internal messages from one Admin to another which will appear in the individual admins inbox. In addition, I would also like there to be a Checkbox which gives the Option to "add this message" to Order Notes. 1). The messaging system should have a link in the main Admin Top Navigation menu with the word "inbox" if a message is created form this area the will need to be a text field to add the order number (optional) and the name of the recipient (Other Admin) of the message and the check box to "add this message" to Order Notes relating to the order number that was entered. 2). In the Sales_Order/View page there should be a new Tab called "messages" here an Admin can send a message to another admin with the Order number already attached to the message. Also, the ability to "add this message" to Order Notes. 3). All messages that have been selected to be added to Order Notes should appear in the Order Notes section and the Comments History section of Sale_Order/View page with the date and name of the Admin that created the message etc... Hope this is clear!