-snip-
I'm pretty sure that the OP is talking about an
Altcoin:
Bitcoin Private (BTCP).
Its addresses starts with "
b1" prefix.
// guarantees the first 2 characters, when base58 encoded, are "b1"
base58Prefixes[PUBKEY_ADDRESS] = {0x13,0x25};
@streamplusThis forum is for Bitcoin development, you can move this to Altcoin Discussion to look for the accurate answers from BTCP users and developers.