The "Kaa...Karuppanukkum" song, with Kamal Haasan and Mallika Sherawat, was to be shot in the USA, but Sherawat had issues with her visa which meant she could not enter the States, so the song's destination was shifted to another destination: Malaysia.
The film was originally meant to release on August 12 2006, but was delayed by six months to release on April 14 2007 - an auspicious date, being the Tamil New Year's Day. Unfortunately, the release was delayed further and the film was tentatively scheduled to release on February 15, 2008. Then legal wrangles forced the film to be postponed a further four months.
The film's tsunami VFX were shot at a 50,000 square foot area of land in which a 100-ft. wall was created near Muttukadu. Six machines, which generated 20-foot-high waves, were imported from the US, for a total cost of Rs. 3.5 crores.
In September 2006, assistant director Senthil Kumar filed a case at Madras High Court, claiming he created the film's story in a script titled "Ardhanari" ("Clones"), and that actor Kamal Haasan and producer Viswanathan Ravichandran had stolen his script. On the basis of this complaint, the Chennai Police questioned the actor and later the High Court sent notices to Haasan and Ravichandran announcing an interim stay on the release of the film. In September 2007, the Court dismissed Kumar's petition, clearing the legal hurdle.