Details here: https://buildd.debian.org/status/package.php?p=bitcoin
...and apparently as far back as 0.4.0 (perhaps always, just not covered by regression tests before that?).
See the "old" links in above page, e.g. https://buildd.debian.org/status/logs.php?pkg=bitcoin&arch=mips
Unfortunately, Satoshi's implementation always depended on little-endianness. As the serialization is implemented through simple memory copying, there is no way it would work on other endiannesses. I am willing to look into this, and improve the situation, but access to a big-endian system would be useful...
I've demoted this from bug to improvement; non-little endian architectures are simply not supported for now.
Related issue: serialize.h its binary format depends on the in-memory sizes of char, int, long, ... On a platform on which these are different from x86, the serialized format will be incompatible.
Closing after #5510