gettransaction (The remote server returned an error: (500) Internal Server Error.) Im trying to get how many confirmations a transaction has. However I just get error when I try to get gettransaction.

http://block-explorer.com/tx/e15e0edd6d6b07531c146a91528ba628b28d37acb28e6a271a563a2284092e16
GetBlock works fine with the transaction here.. also getrawtransaction works.

However when I try gettransaction I get this error.
The remote server returned an error: (500) Internal Server Error.

This is how my request looks like
{"id":"0","method":"gettransaction","params":["e15e0edd6d6b07531c146a91528ba628b28d37acb28e6a271a563a2284092e16"]}

Any ideas of what Im doing wrong here?
Doesnt work for transactions that are not your own.