Hi Cachalote,
I have a small collection of DS catalogues, I don't have all of them so I can't work out any discontinued dates.
I have a German DS catalogue 2003/2004 and sets 7668 Piraten-kapitan and 7667 3 Piraten are listed as being new items.
In a UK DS catalogue from 2000 set 7243 3 Pirates are listed as being new for that year, so 1999 could of been the year for its German release.
I'm sure I have a catalogue with 7228 in it I will have to search for it a bit later on.