Actually Sandman is right. Both uses are acceptable. If they weren't, you would find phrases such as the following being acceptable, but amusing:
"None of us is going to town." Contrast that with : "None of us are going to town." The pronoun "us" indicates plurality, and makes "are" a more appropriate choice.
"None are college educated." Okay, "None is college educated." can be used, but it isn't very prosaic. I could have said "None of them are college educated." which would have given me two nouns indicating plurality, but I didn't, choosing to shorten the sentence. Besides, at the start of that phrase, I used the noun family, which can be construed as either singular or plural. I chose to use the plural meaning, for that allowed me to pair it with "are" which made the sentence more pleasing to the ear.