MSU has an ordinance,but it has an exception for except as otherwise allowed by state or federal law,meaning as long as your lawfully carrying,they wont bother you.
ordinance # is 18.01
2009 - 2010 Spartan Life student handbook and resource guide (online) on page 106 still contains the following.
FIREARMS OR WEAPONS
(Ordinance 18.00)
.01 No person shall possess any firearm or weapon anywhere upon property governed by the Board. Persons residing on property governed by the Board shall store any and all firearms and weapons with the Department of Police and Public Safety.
.02 No person shall possess any chemical, or other dangerous substance or compound, with the intent of using the same to injure, molest, or coerce another, anywhere upon property governed by the Board.
.03 The use of any firearm or weapon is prohibited upon property governed by the Board except those areas specifically set aside and supervised at range facilities, or as part of the regular education process, or as outlined in Ordinance 37.02 (wildlife) and its subsections.
.04 This ordinance shall not apply to Police Officers and other legally established law enforcement officers.
—Board of Trustees
—September 15, 1964
—Revised December 11, 1987, December 10, 1994, April 14, 1995, April 12, 2002
This differs from the MSU Board of Trustees Ordinances, Ordinance 18.00, which contains the exception you mention. I do not know if this is an oversight or if the Student handbook is uncoupled from Board of Trustee Ordinances.