...
The 32-bit version (afstokens.zip) is for Intel Core Duos, and the 64-bit version (afstokens-64bit.zip) is for Intel Core-2 Duos (you can determine which you have by looking at the "Processor" line in the "About this mac" window under the Apple menu
6. Download the OpenAFS Contextual Menu Plugin from:
http://oit.ncsu.edu/macintosh/contextualmenu
7. Copy the Contextual Menu Plugin to Mac HD - Library - Contextual Menu Items