Spawn menu black icons

On any of the addons that i have downloaded, such as the stranded model pack or phx, the icon in the spawn menu is just a black square. The model will spawn fine though. What causes this and how can you fix it.

Any help would be appreciated.

Can you give us the specs of your computer, as well if it is a PC or a Mac?

processor:Intel Core i7 CPU 930 @ 2.80GHz
graphics:ATI Radeon HD 5670
OS:MS Windows 7 Home Premium Edition