hmm.. I know that there is a jumper in the A4k that tells the computer if the DF1: is internal/external and if it is DD or HD.
might be something like this your problem is about. But i guess if you can't tell the A2k that the internal DF1: is a HD drive it will only use it as a DD drive.
I don't know if you can use this, but it was just something I remembered on my A4k.