'CSI' Star Marg Helgenberger -- I'd STILL Work with Bieber ... Despite His Bratty Cameo

"CSI" star Marg Helgenberger would be HONORED to work with Justin Bieber again -- despite what she said last year ... that the singer was an intolerable "brat" behind the scenes of her TV show.

In case you didn't know, Bieber acted in one of the greatest episodes of "CSI" history -- a cameo that culminated in his character getting shot up in a comically excessive hail of gunfire.

But Helgenberger wasn't his biggest fan -- telling a French radio station shortly after the episode aired ... Bieber "was kind of a brat" on set, locking a producer in a closet and even punching a cake.

Now, Helgenberger appears to have had a change of heart. The other night in L.A., we asked if she'd ever like to work with Bieber again ... and she replied with an enthusiastic "OF COURSE!"