1. PROCESS raspberries in a blender or food processor until smooth, stopping to scrape down sides. Pour puree through a fine wire-mesh strainer into a large container, discarding raspberry seeds. Set puree aside.
2. BRING 3 cups water and sugar to a boil in a saucepan, stirring often. Remove from heat; add tea bag. Cover and steep 5 minutes.
3. REMOVE tea bag with a slotted spoon, squeezing gently; cool tea mixture.
4. STIR together tea mixture, raspberry puree, grape juice, and lemon and lime slices. Chill.
5. STIR in orange soft drink, and serve immediately over ice.