I installed a clean fresh install of the lastest version of ZC downloaded from zen-cart.com and as before created some cat's and products. I get the same results as before, a internal 500 error??? when using the Attributes Controller as soon as I click on a cat with a product in it.

Apache version 1.3.37 (Unix)
PHP version 5.2.1
Operating system Linux
Kernel version 2.6.9-46.ELsmp
MySQL version 4.1.21-standard
Machine Type i686