> len(base64.decodestring('x'72)) == 54

Yeah, I thought about that. But I tested it and that wasn't it:

>>> hashpw('x',s) '$2a$05$YTnGVPqoxIgfmWrHAxHqhegbOHvVmK8y9bvOwNlOUVEruX9NjPBJy'

>>> hashpw(chr(ord('x')+128), s) '$2a$05$YTnGVPqoxIgfmWrHAxHqhesvRgqg0bHauZJ3SrAc2oRwZ3XF46hE2'

> subkeys can be up to 72 bytes long

That makes a lot more sense.