Assigning Settypes to Product Categories

Hi,

I'm about to start building up hierarchies and categories for my CRM Solution (using CRM 5.0). There are a couple of generic Settypes that should be working irrespectively of product type (e.g. Material or Service). One of those settypes is COMM_PR_SHTEXT - but I cannot find it, regardless of which Product Type I've chosen. Is there a step I'm missing. What I've done is:

1. Created a new hierarchy

2. Created a "root category" where I've disabled the possibility to assign products. No product type chosen.

3. Under this root category, I've created other "sub categories" with Product Types assigned.

When I try to assign Settypes to these categories, the settype COMM_PR_SHTEXT does not show up...

Any ideas what could be missing?