how to create a tagging sys like in phpfreaks forum with tinymce

[narutofan]

Hi,

i need to create a phpfreaks style tagging system in one of my projects and i'm stumped at how to get user input value at keypress after they type the "@" symbol in tinymce editor and i need help on how to create a phpfreaks style dropdown list and how to capture the clicked usernames. i think they are using tinymce3 editor to post updates. can anyone help me regardiing this problem.