From the event organizers:
This years Christopher Street Day in Trier was held from June 18 to 21, 2009. We (the German initiative against homophobia "Aktionsbuendnis gegen Homophobie") were involved in the organisation of this event as a whole and were also present with an information booth. We did, however, get most attention with our WhiteKnot.org-initiative where we provided almost every visitor of our booth with a white knot.

To learn more about this group, check out their site.