Role fields of an association display with a leading '-' (minus). (#280)
In a class diagram the role fields of a composite or aggregate association (those on the opposite side of the association line from the multiplicity) display with a leading '-' (minus).
There doesn't appear to be any way to remove it.
(This is a re-occurrence of a bug I raised on March 13 2013. Is there any way for users to reopen a previously closed bug?)