Will version 2.5.1 and 2.8 of the CodeWarrior for Symbian OS Pro version support development using the Series 80 SDK or do I need to upgrade to 3.0?
I don't know much about S80, but the general rule is that you need CW 2.8+ for OS 8.0 and you need CW3.0 for OS 8.1 and greater.
Series 80 SDK works with 2.5, 2.8 and 3.0, because it uses Symbian OS 7.0s. The best IDE versions for the Series 80 SDK are 2.8.x or 3.0.
This information is written to the Release Notes of the Series 80 SDK packet