In most foreign releases of the film, references to Madame Rose being a kathoey (male-to-female transsexual) have been removed, in spite of the fact that the actress playing her (Jing Xing) is also a transsexual. Her survival at the end of the movie has also been cut, instead indicating that she is killed.
According to the director on the special edition DVD, the continuous fight scene took five full takes for a variety of reasons, including stunt objects not breaking and the stunt mat not being in place in time. The five takes were filmed over a one-month period.
Three cameos: Tony Jaa's father appears at the Songkran scene; a Jackie Chan double in the airport, intended as a tribute to Jaa's idol; and Thai rock star Sek Loso appears prominently in the foreground in one scene drinking his trademark energy drink, which was tied up in a promotional relationship with the movie in Thailand.
The part where he jump kicks and breaks the lamp on the lamppost making the bad guy run in fear is an homage to the Bruce Lee film, Way of the Dragon, where he does the same thing to a ceiling light after taking down some bad guys, causing the last of to run away in fear.