If your GRSS mod is blocking whispers, or if you're mod isn't autosnapshotting Ulduar Bosses, or if the Emblems from Ulduar are prompting you for loot costs, it means you're not running the new version of the GRSS.

If you use the GetGRSSDKP program before each raid (like you should), it'll tell you your version is out of date.

Or you can just download the newest version.

Also, make sure your other mods are up to date. So far, the only explanations found for blocking whispers with the new versions of the GRSS (0.995) are other mods that work with the chat system but hadn't been updated.

--
It's all in the reflexes.