Greetings,
Does Lightroom use ACR to determine what RAW files it will import? I have an example. Using a Mac, PhotoShop CS2, and ACR 3.6 I can read both the Digilux 3 and Pansonic L1 RAW files. These are <apparently> twin cameras. However, using Lightroom Beta 4 I have no problem with the Panasonic L1 RAW files but it will not read the Digilux 3 RAW files. What does work is to convert the D3 RAW files to DNG using ACR 3.6 convert and then loading the DNG files into Lightroom. My guess is Lightroom has it's own list of supported RAW files.
Cheers. Terry.