The topic says it all.
Enabling ‘Flat Catalog Product’ causes the getSku method to return a null/empty string value, and that kind of messes up my template and image handling (most of the images are loaded based on sku).
- enabling ‘Used in product listing’ option in attribute definition (to no avail -> SQLSTATE[42S22]: Column not found: 1054 Unknown column ‘e.’ in ‘field list’)
- putting ‘sku’ in application config (local.xml)
- rebuilding catalog and clearing the cache
Funny thing is, custom, non-system attributes are retrieved and can be accessed just fine if specified in application configuration.