Not a bug so much as a design decision. The Satoshi Bitcoin implementation does not work on big endian architectures and likely never will.
If you want to be a BE Bitcoiner, your best bet is to use one of the other implementations like BitCoinJ or BitCoinJS.
I'm not that sure the codes relies on LE that often. The serialization routines for integers, uint160, uint256, and the fact that pointers to those structures are passed directly to hashing routines, would need to be adapted. That does seem reasonable (though not high priority) to change, unless there is a ton i'm forgetting now.