GNOME 1.2, used in Debian 2.2, used the DB library version 2. GNOME 1.4, used in Debian 3.0, uses the DB library version 3.
The files used by these versions are not compatible.
GMC uses the DB functions to create the file /.gnome/metadata.db to handle desktop links et al.
So this file has to be recreated, otherwise, the links use the standard icon, they can not be changed, and new icons can not be created.
Convert the metadata.db file for all regular users. Only available for root.