WASHINGTON (AP) - In view of fears that North Korea is developing chemical weapons, the U.S. might be willing to share its anthrax vaccine with ally South Korea, Secretary of Defense William Cohen said Tuesday. "We do believe that the North Koreans and others have been in the process of developing both chemical and biological weapons, and that we ought not to take any chances that assumption or information is in error," Cohen said at a Pentagon news conference with South Korea's defense minister, Cho Song-tae. The Pentagon undertook a program in 1997 to vaccinate all active duty and reserve military personnel against anthrax, an infectious bacterium it fears could be used by Iraq, North Korea or terrorists as a biological weapon.