Version: (using KDE 4.3.1) Installed from: Ubuntu Packages Currently it is possible to define filters to tag mails matching certain criteria to be tagged important, spam, old, etc. However, it is not possible to assign user-defined tags like this, although user-defined tags can be assigned manually. Please add the possibility to assign custom tags via filters, it would help a lot!
Implemented for KDE 4.4 *** This bug has been marked as a duplicate of bug 171204 ***