It's Dutch Nickelodeon. =)
They already have Season 4 and the 1st Movie (not sure if they have the Second Movie yet)
While USA/Canada hadn't yet.
Still hadn't see any Winx Club Commercial on Nickelodeon in America. ^^"
Germany Nickelodeon is starting to have Winx Club Series Re-run (again, they already have Season 4, 1st Movie, and 2nd Movie in process of airing May 5, 2011)
*Remember, Dutch and Germany have their own Nickelodeon Station, it's not under the US (But Nickelodeon is created from US). It's their own language and rights to broadcast their shows ^^".
(I don't think I explain it right since it's confusing...>.<")