Re: Multiple public adresses for one private key?

The private key in Wallet Import Format (WIF) as most of us are used to seeing it actually has 3 important parts.

https://en.bitcoin.it/wiki/Wallet_import_format

(1 byte) A version number.
(32 bytes) The ECDSA private key.
(4 bytes) A checksum.

By changing the version number, you can generate different bitcoin addresses (one for an uncompressed public key, and the other for a compressed public key) with the same ECDSA private key. This will result in a different WIF (both the version number and the checksum will be affected) for that private key though, so when viewed in the typical format it will appear to be a different private key.