A federal judge has ordered a mental examination for a woman accused of threatening Michelle Obama, due to arrive in Honolulu today with the president and family.

Kristy Lee Roshia, 35, is charged with threatening to kill the first lady in a telephone call to the U.S. Secret Service's Boston field office last month.

“;We will take very seriously any threat against the president or member of his family, especially since he's coming to Hawaii,”; said Elliot Enoki, first assistant U.S. attorney.

Obama and his family are expected to spend the Christmas holiday on Oahu.

The Secret Service said Roshia told its agents she knows where Obama will be staying and that she traveled here in September to protect him.

The judge ordered the mental exam to determine if Roshia is fit to stand trial and whether she was sane at the time of the alleged threat.

In 2007, Roshia pleaded guilty to threatening a Secret Service agent at the agency's headquarters in Washington, D.C.

A Superior Court judge there sentenced her to 180 days in jail, followed by probation. The judge also ordered Roshia to a undergo mental health examination and treatment.