It's important to remove old "FB" requests because a large backlog of pending requests will prevent you from adding more friends. The "DW" list of pending invitations (on your Teammates page) , on the other hand, has no effect on the game and can be ignored.
Here's a workaround:
1. Install this facebook application http://apps.facebook.com/friendrequests 2. It will search & displays "My Pending Requests" 3. View each profile by clicking on it's name. (don't click on "Remove Request" on the right, it will not work) 4. When the profile loads click "x" next to "Awaiting friend confirmation" at the top of the page.
For those who are blocked for sending or receiving friend requests (Pink Box Warning):
5. IMPORTANT: Wait for a day or two after removing all the "pending requests". In between don't try to send any request. 6. Then you will be able to send friend requests.
I can't stress step 5 enough. Be patient, the server has to update your 'pending' list for the request block (Pink Box of Death) to go away. After you get your pending list down to under 100, you should be able to invite 20 or 25 ppl a day.
Hope that helps. PS: Use Firefox, and keep Flash updated.