The Council on American-Islamic Relations (CAIR) has called for a North Caronlina court to allow witnesses to swear on the Holy Scripture of their choice, including the Koran. Current law there requires witnesses to place their left hand on the "Holy Scriptures" and raise their right hand while swearing to tell the truth in their testimony. A presently legal alternative is to affirm that one will tell the truth. This is usually used by those people whose religious beleifs prevent them from taking an oath.
CAIR argues that the term "Holy Scriptures" can be taken to mean the Koran as well as the Christian Bible. According to CNS News, "North Carolina's Administrative Office of the Courts last week issued a preliminary opinion saying that state law allows people to be sworn in using a Koran rather than a Bible."
In spite of my political leanings, I agree with CAIR on this one. As long as swearing on the Koran is not mandatory, I don't see the problem with using the witnesses' own Holy Scripture if he or she chooses.