Ok, so I'm working with images that are used in an existing program. Some of the images, like this one:

actual file here: http://invisiblecarrot.com/images/im/odouls.tga
are regular uncompressed TGA's that IM detects with an alpha channel. Now, if I convert straight to PNG, I get this:

But that's ok, I use these commands (and the Ruby equivilent) to get the correct PNG:
convert odouls.tga -alpha off odouls_alpha_off.png
convert odouls.tga odouls_inverse_alpha.png
composite -compose minus odouls_alpha_off.png odouls_inverse_alpha.png output.png
Now, some TGA's are run across are compressed, like this one:
http://invisiblecarrot.com/images/im/package.tga
The program I'm messing with sees the TGA above as this:

So the app is detecting an alpha channel. But If I pull an "indentify -verbose package.tga" IM doesn't detect an alpha channel. If I convert it to a png, the supposedly transparent sections are blacked out. The only images I've come across like this are the compressed TGA's. Photoshop doesn't see the alpha in the compressed TGA's either.
So is whatever app the person is using to produce the TGA's doing something weird? I initially thought that the app was using a color-key or something like that, but it specifically mentions the image having transparency info in it's "diagnose" section:
Bitmap image loaded successfully.
Bitmap contains transparency information.
13.1% of the image's pixels are transparent.
Anyway to get IM to see the alpha channel in these TGA's? Thanks for your help!
EDIT:
I'm using ImageMagick 6.5.6-8 2009-10-03 Q8 OpenMP.