I didn't know you could define multiple components in a single file.
You can learn a lot of things by looking through the wiki example...

@Name("converters")
@Scope(ScopeType.APPLICATION)
public class Converters {
...
 @Name("importerConverter")
 @org.jboss.seam.annotations.faces.Converter(forClass = Importer.class)
 public static class ImporterConverter implements Converter, Serializable {
...
}