Blizzard has updated their «Known Issues» list for Cataclysm Classic. These issues include Death Knight's Blood Presence and Frost Presence not working as intended, Heroic Burning Crusade dungeons deactivated, and the PvP Resilience stat not working.
AddedClasses Death Knight Blood Presence is increasing the chance that the Death Knight takes a critical strike.
Frost Presence and Improved Frost Presence are not increasing Runic Power gains. Dungeons and Raids Players cannot enter many Heroic Burning Crusade dungeons. Ulduar Yogg-Saron does not spawning any clouds.
Enemies in Ulduar are hitting for much more damage than intended. Ice Crown Citadel Blood Queen Lana'thel may sometimes refuse to bite. Leveling Opening treasure chests and professionally gathering does not grant the intended experience. Player versus Player Resilience is providing about 20% of its intended effectiveness.
This should be fixed with weekly scheduled realm restarts. Removed/Fixed Some heirloom items unintentionally have spell power. .