OS X Leopard (10.5) insists on having Helvetica and Helvetica Neue installed

This is a major pain in the ass for the design industry

Here are some solutions

http://www.macworld.com/article/61302/2007/12/helvetica-leopard.html

http://dl.extensis.com/downloads/SC/EN/P/Fonts_Best_Practices_in_OSX.pdf#page=9