UILabel not rendering division sign (even in fonts that support it)

Hey gang. So, I've got a UILabel into which I'm putting an NSString containing one of four unicode characters for plus, minus, multiplication and division, the basic four operators. The divi开发者_JS百科sion symbol I'm looking for is the obelus (\u00F7). Even in Helvetica, which both supports the obelus character and exists in iOS, this character renders incorrectly in the UILabel:

Any thoughts on why this could be?

~Mikey