Can wishing a teacher 'Merry Christmas' lead to a suspension?

According to the National Report:

Timothy Dawson, a 9-year-old student at Argon Elementary School in San Francisco, CA, Timmy was suspended from school for a week because he wished his teacher a 'Merry Christmas.'

The little boys teacher, a staunch Atheist, was offended at the 4th graders display of Christmas spirit and had school staff suspend him.

Poor Kid.