(Corrects to Saudi-Iraq border, paragraph 8) By Saud Mehsud and Mubasher Bukhari DERA ISMAIL KHAN, Pakistan, **v 17 (Reuters) - A splinter group of Pakistan's Taliban has pledged support to Islamic State (IS), a spokesman said on Monday, in a**ther indication of the appeal of the Iraq- and Syria-based jihadist group in a region traditionally dominated by al Qaeda and local insurgencies. Jundullah an**unced its backing after meeting a three-man delegation representing IS led by al Zubair al Kuwaiti, the group's spokesman Fahad Marwat told Reuters. ...