I don't think, it was anything against Volandri whose stomach was hurting btw. He seemed to discuss 1-2 umpire calls. Not like Volandri needed to care about that, since he lost the set. Maybe they get along well, I don't know.
Goodness knows why he didn't speak to the umpire, then. Or get the marks checked at the time.
I thought he was irritated about how long Volandri was off-court when he went off the first time to get treatment from the trainer. I assumed it was something to do with that.