A few things, or rather observations.
No matter the duress, or stress put on a person, a person's dialect or speech does not change. If anything, it reverts to his/her original mother tongue/tone/dialect, whatever have you. So if we want to believe that he adopted that tone under torture and stress, then it sort of proves the point of most members within this thread that he does not speak like a person whose origins are Pakistani, especially that of a person who supposedly is illiterate.
Take for example the immigrants living anywhere in the world, they may adopt the language, but certain beliefs (reference of this fellow saying Bhagwan which a follower of Hindu faith would refer to in the most dire moments, vs. a muslim who would blurt out Allah when in extreme need) and original accent (for those that retain an accent) remains, thereby giving up his/her identity to those are well versed with that distinct accent. Just as a hindi speaking person would recognize someone else who speaks hindi from dialogue, a punjabi to a punjabi, an urdu speaker to an urdu speaker, and so on.
Secondly, wikipedia is not a genuine source. It is not taken as being the absolute fact, although many refer to it for reference.
*Thirdly, to tout that Present Pakistani Govt. has accepted his origin is sort of like convincing the blind man that he is lying and can indeed see if he only tried a little harder. The reason for me using that analogy is because the current Govt does not really enjoy a prime credibility, and certain politicians are often coined as doing the bidding of "allies" on more occasions than putting the interest of the nation first, be it Central Govt or Opposition. It's our dirty laundry, and an ugly fact we live with on a daily basis, but lets face it; our current President is not exactly seen by many as Presidential material, neither is his cabinet seen as a dignified team of politicians out to serve the nation. So, for those us who refer to the Pakistan Govt acceptance should in all honesty (if the sincerity is present in discussing the matter) should account for that view of a majority of Pakistani public. *
As for the individual in question, may he get all that he deserves for his actions. May the victims of Mumbai attacks rest in peace.
Dear Teggy ,let me take this bolded version only because other statements regarding his accent other things can be left to space.
The current Pak government was first in action in refusing to accept that he was a pakistani and then in Jan 2009 almost after two months of the attack it agreed that Kasab was a Pakistani.Let me categorically make it clear that no government can fool around the entire world (let alone Pak people)with such an acceptance.Obviously the case was being handled by various international agencies like FBI and MOSSAD and Kasab's interrogation details,GPS mapping,Recorded phone conversations and other dossiers had been shared among all these agencies.Do you think a government could blind heartedly deceive all the people in this world(again this time including Pakistani people) ,saying Kasab is a Pakistani?If it was not Pak government ,a proper US intervention(with foul proof) could have persuaded Pakistan accept the fact that he was a Pakistani.I guess ,Pak government was given a chance to escape an early embarassment.
Mr.Nawaz Sheriff's statement (that link I have provided) itself shows that Pak government was in hurry to hide something.The moment Kasab's details started coming out in open the authorities tried to hide his family members and erase any proof of his whereabouts.Pls recall the fact that it was a Pak T.V channel,GEO ,had conducted an early media investigation in to this case and had aired about his exact whereabouts.I comment the way an unbiased coverage GEO had conducted .Pls also remember that the journalists and reporters who tried to unearth more details abt Kasab and his family were roughed up by the locals.