Pietersen was dropped from the Test squad in August after saying he did not find it easy being in the England dressing room and allegedly sending derogatory text messages about his team mates.
But he is now back in the squad and added: "The dressing room is absolutely fantastic.
"We're sticking together really well, all helping each other out, and not letting things get on top of us.
"If anybody is going through a rough time, everybody else is right behind them. It's a very united dressing room at the moment, and it will be even more so if we manage to pull off a brilliant victory tomorrow."
