Rapper T.I. got in some serious trouble with prison officials this weekend — after guards caught him getting “frisky” with his wife during visiting hours … TMZ has learned.

T.I.’s wife Tiny confirms … the two were in a room together during regular visiting hours at Arkansas State Prison when Tiny made like Michael Jackson … and beat it.

According to prison guidelines, inmates are allowed to kiss and embrace at the beginning and at the end of a visit as well as hold hands — but “the inmate’s hands must remain in plain view of Visiting Room staff at all times.”

Tiny tells them T.I. was immediately reprimanded and sent to a “Special Housing Unit” — which consists of more security and less freedom.

Tiny says she hasn’t spoken to T.I. since the incident — but she’s hopeful she’ll be allowed to visit again soon … as long as she keeps her hand to herself.