How to hide some fields by category

[plhostis]

hello

i want to hide some fields depending of the category ?. How can i do ? do i must write a custom function ? is there a repository of customs functions source code ?

thanks

[SystemCorp]

I would also be interested in this, but I haven't been able to find any implication this would be a simple change.

[mcain]

bump.. interested with this also.. anybody know how to do this?