I've noticed the behavior I'm about to describe since patch 1.05 was installed. Now the the Playstation Store is available again, I was able to experiment and find out more.
Originally I'd noticed that installing the 1.05 patch seemed to cause Dead Money to be invisible to the game, it did not show up under Downloadable Content after patching but Classic Pack was still there. I thought perhaps that Dead Money was corrupted somehow, and wasn't able to reinstall it until this morning when the store became available. That didn't fix it. I also found that Honest Hearts installed freshly was not detected by the game.
I deleted all the game data and DLC from my PS3 under Game Data Utility and then installed the game freshly, patched again to 1.05. I downloaded Dead Money again and installed it, then fired up New Vegas - the game could see Dead Money properly now.
I quit and downloaded Honest Hearts, installed it and fired up New Vegas - now Dead Money and Honest Hearts were detected properly.
I quit and downloaded the Classic Pack and installed it. I fired up New Vegas and Dead Money and Honest Hearts were no longer detected by the game. The Classic Pack was detected properly.
I'm unsure if this has anything to do with it, but the Classic Pack shows up in the Game Data Utility as "Fallout: New Vegas DLC - (US)" rather than being lumped in with Dead Money and Honest Hearts under "Fallout: New Vegas DLC - (CA)". I could tell this after deleting both DLC items in Game Data Utility and then re-downloading (again) Dead Money and Honest Hearts and installing them (now I only have "Fallout: New Vegas DLC - (CA), so presumably the Classic Pack is US content).
In short, as soon as I install the Classic Pack, all other DLC seems to get b0rked. If I want to play Dead Money or Honest Hearts, I cannot have the Classic Pack installed. I'm unsure if this is also the case with other retail packs that were available when the game came out.
Hopefully that's enough info for the developers to fix the problem. I'd suggest to other users having similar issues to remove any of the retail pack DLC add-ons or all the DLC, then re-download and re-install Dead Money and Honest Hearts, and not install retail packs until the issue is solved. It's free to re-download DLC once you've paid for it.
