I have run bitcoind and have several accounts. How do I get the immature balance of one account using RPC calls (if possible) ?
listtransactions command, you can see your immature coinbase transactions listed with category
listtransactions appears to include both spent and unspent transactions in general, but since immature coins cannot be spent, that shouldn't be a problem.
Since accounts are now deprecated, you can get the immature balance for the entire wallet with
getwalletinfo; look at the
getbalance does not include immature coins.
With the getbalance command you can specify an account and minimum confirms, I'm assuming my immature balance you mean account balance containing unconfirmed transactions. By default it's at one.
getbalance [account] [minconf=1]