Following pl interwiki you'll find more (yes! I'm a Pole!); Wiktionary page is a good source as well.
On 'pedias since July 13, 2002. Contributing mainly to Polish one (first recorded edit on July 24, 2002). On English adding interwiki and fixing minor things - that's not true that it was always like this ;-) (first edit on August 11, 2002)