Can't remove sticky post category from RSS feed

Hello all,

I have just found your forum after days of searching for help. My problem is this.

I have set up a feed from my blog and everything is great, but as its a wordpress site its also bringing in other posts that dont belong in the feed.

I have managed to remove most of the unwanted post categories but one of them is a sticky post and wont budge from my feed.

Heres how I removed the categories in my feed:

http://joebloggs.com/blog/feed?cat=-1,-5,-7,-6,

Have I done something incorrectly? If anyone has any ideas, I'd love to hear them.

Many thanks
Nathan