bitaddress.org provides the private key in "Sipa Wallet Import Format" and MtGox is expecting "Standard Format".
I'm working on a new tab for bitaddress called "Wallet Details" it will have one input box for the private key and I will auto-detect the format and display the private key in the various different formats including the "Standard Format" required by MtGox.


THANKS to MtGox for this super cool feature of private key redeeming!! I hope they add an auto-detect for all the different private key formats.

Here is what I have tried so far:

I entered the mini private key S4b3N3oGqDqR5jNuxEvDwf and got the response "Private address added to your virtual wallet with address 1GAehh7TsJAHuUAeKZcXf5CnwuGuGgyX2S. There was no coins in there, maybe you did a typo?"  This is the correct public key address and there are no coins at this address.  So far so good.

I entered the hex private key for the same key 0c28fca386c7a227600b2fe50b7cae11ec86d3bf1fbe471be89827e19d72aa1d and got the response "Your private address could not be redeemed (already redeemed?)".  I guess this is the expected response and it proves that they calculated the same account for this version of the private key.

However, when I enter the WIF 5HueCGU8rMjxEXxiPuD5BDku4MkFqeZyd4dZ1jvhTVqvbTLvyTJ for the same private key it calculated the wrong public key address.  So there appears to be a problem/bug when using the WIF.

I reported this bug to Mt. Gox.

I then used both a real mini private key and a real hex private key to attempt to import Bitcoins from active accounts (opened physical coins).  In both cases it calculated the correct public key address and found that there were Bitcoins in the accounts and promised to import them into Mt. Gox.

The Bitcoins were eventually moved off the accounts for the private keys I entered into Mt. Gox and placed on new accounts withing Mt. Gox.  This proves that they sweep the value off the imported private keys so there is no way to reuse the private key to send Bitcoins out of Mt. Gox.

See http://blockexplorer.com/address/13MsUf2Nnowoj8gdZBfBSyBJzVcC1R7hZA

And http://blockexplorer.com/address/13MT4QvExmajXAYqKQeMXAh9saVTVP6f6a

Both (one from a mini key and one from the hex key) showed up in my Mt. Gox account:  The notation looked like this:

This shows both the notes I put in when I imported the key (first bits of the original public address and the private key type used) and the new public address the Bitcoins were swept into.

"Auto sweep" also works.  I added 2 more Bitcoins to one of the addresses I imported via private key.  The amount was then automatically swept from the imported private key account and transferred to yet another new account inside Mt. Gox.

See http://blockexplorer.com/address/13MsUf2Nnowoj8gdZBfBSyBJzVcC1R7hZA

After sending 4 opened coins (2 using mini key and 2 using hex key) and then sending two more Bitcoins by sending them to one of the opened coin accounts using the "auto sweep".  My Mt. Gox account shows:


Very nice new feature!

If you don't mind telling your private key to Block Explorer, you can use their API:

Example:
Address: 13mWJ7RtAoMTB6nYTWouHSc8KLfpUWZskY
Privkey: 5JSnvLmCsFDye4QMbYE1fsyGAPbpr1XjyBuGJpqVfdvuz2kmuo6

Go to https://blockexplorer.com/q/addresstohash/5JSnvLmCsFDye4QMbYE1fsyGAPbpr1XjyBuGJpqVfdvuz2kmuo6
and the hex that it spits back is 52E417A1818758EBC3E1C595BF0DCA0C9F29A0E1087D5B01456F43819CFBD401

And if I go to Mt. Gox and try to redeem it, it says "Private address added to your virtual wallet with address 13mWJ7RtAoMTB6nYTWouHSc8KLfpUWZskY. There was no coins in there, maybe you did a typo?"

I'm sure that there are ways of doing it with openssl or python or whatnot locally, but as long as you trust the Block Explorer site to not do anything nefarious with your private key before you have a chance to redeem it, it ought to work for you until Mt. Gox supports the import format directly.

Boom that worked!!! Thanks bud!

pywallet.py --info --importprivkey 5JSnvLmCsFDye4QMbYE1fsyGAPbpr1XjyBuGJpqVfdvuz2kmuo6

will return:
Address (Bitcoin): 13mWJ7RtAoMTB6nYTWouHSc8KLfpUWZskY
Privkey (Bitcoin): 5JSnvLmCsFDye4QMbYE1fsyGAPbpr1XjyBuGJpqVfdvuz2kmuo6
Hexprivkey: 52e417a1818758ebc3e1c595bf0dca0c9f29a0e1087d5b01456f43819cfbd401

I have confirmed that MtGox now accepts private keys in "sipa format".

Interesting.  That particular address and public key pair is just the test pair from the wiki here:  https://en.bitcoin.it/wiki/Mini_private_key_format


So, it is not any of my personal addresses or public keys (whew).  But it interesting that it showed up.  My guess is that Mt. Gox may be using that test pair for testing and somehow their testing went astray?