‘FRESH PRINCE’ STAR RIPS WILL SMITH

The woman who played the original Aunt Viv on "Fresh Prince of Bel Air" says there's a damn good reason she wasn't at a recent reunion dinner with the rest of the Banks family -- she HATES Will Smith.

15 years after the show went off the air ... Janet Hubert tells TMZ she's still upset with the way she was fired from the show ... and blames the whole thing on Smith himself.