Are nonextremal black holes supersymmetric?

In field theories, it is generally thought that BPS solutions are in one-to-one correspondence with supersymmetry preserving solutions. While extremal Reissner-Nordstrom black holes are known to be BPS, it has long been thought that their nonextremal counterparts are not. It is shown that these nonextremal black holes are indeed BPS solutions, but that there is no supergravity theory that contains them as solutions that preserve a fraction of the supersymmetry