Character Name Restriction?

When I enter the name "Alexander" for a new character on Olothontor's table, the character sheet gives an error saying "Please choose another name". I don't have another character named Alexander. The name works on my table.
My browser version is: (do not change)
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/40.0.2214.115 Safari/537.36

Looks like someone else had a character named "Alexander" on Olonthor's table.