Twenty-six-year-old Joel A. Yodis pleaded no contest to a charge of terroristic threats in the March 2008 incident.
Authorities say the Phoenixville man became angry when classmates laughed at him. An affidavit alleges he threatened to kill them, using his hand to imitate firing a pistol.
A student notified a professor and the college was placed on lockdown for two hours until Yodis was located at the school library.
Defense attorney Alan Goldberg says Yodis was just gesturing, not pretending that he was holding a gun.
Goldberg says the threats Yodis made were just mumblings that weren't meant to be heard by others.
Information from: Intelligencer Journal, http://www.lancasteronline.com/pages/paper/sundaynews/