Sean Kingston in Hospital -- Awake & Alert

6/3/2011 5:30 AM PDT

Sean Kingston in Hospital -- Awake & Alert

Sean Kingston still has a breathing tube in his mouth so he can't talk -- but sources close to the singer tell TMZ, he's awake and alert in his hospital bed ... and he's getting better every day.

According to sources, Sean's friends and family have been inundating his hospital room in Miami since the accident -- and the "Beautiful Girls" singer is communicating through nods and sign language.

It's a big improvement since the day of his jet ski crash on Sunday -- when his injuries were so bad, he had to be treated in the trauma ward ... before he was transferred to the ICU.

Last we checked, Kingston was still in critical condition -- and doctors expect to keep him hospitalized for another couple of weeks.