David J. Ajemian ’83 is a different sort of celebrity than Harvard is used to producing.

Ajemian, who was arrested in November 2007 when he attempted to enter a taping of Conan O’Brien’s NBC show, “Late Night with Conan O’Brien,” plead guilty in April to charges that he had stalked the late-night comedian, who is a member of the class of 1985.

In Manhattan Criminal Court, Judge Rita Mella ordered him to pay a $95 court charge and to avoid O’Brien for two years.

Court papers reveal that Ajemian sent threatening messages to O’Brien’s home, office, and workplace, in which he suggested that he was one of the comedian’s “most dangerous fans.”

Considering it a “delayed vocation,” Ajemian joined the Roman Catholic priesthood later in life than most, and was ordained in Massachusetts in 2001. Until his arrest, Ajemian served in the Boston area’s St. Patrick’s parish.

The New York Times reported after his arrest that some of Ajemian’s letters to O’Brien were written on parish letterhead.

Terrence C. Donilon, spokesman for the Archdiocese of Boston, said that even after April’s controversy, Ajemian remains a priest of the Catholic Church, although he has been placed on administrative leave. The spokesman said he did not know when Ajemian would return.

Ajemian’s lawyer declined to give comment on the outcomes of Ajemian’s trial, but did acknowledge that his client had been treated for mental health problems in the past.

—Staff writer Charles J. Wells can be reached at wells2@fas.harvard.edu.