T.I. -- Rapper Talks Suicidal Jumper Off the Ledge

It all went down earlier this afternoon -- when cops responded to a 911 call about a man who was threatening to jump off a building in downtown Atlanta ... the same building where Ryan Cameron's Radio Show on V103 is based.

We're told T.I. heard about the jumper on the radio -- and called Ryan Cameron to see if there was anything he could do to help out with the situation.

Ryan Cameron tells us ... he told T.I. to roll over to the building, where the rapper met with police and recorded a heartfelt video message which cops then played for the man on the roof.

We're told after the man saw T.I.'s video he agreed to step off the ledge ... and met T.I. in the lobby, where the two were able to talk things out.

Ryan Cameron also tells us that cops informed the radio station that they will not be pressing charges against the man.

Calls to T.I.'s reps have not been returned.

UPDATE: Sources have revealed to TMZ what T.I. said in the video message: "Nothing is that bad. Nothing in life is worth taking your life. I'm here to help you. Please come down to talk to me."