Bitcoin v0.3.12 was released on SourceForge on September 7, 2010, one of the rapid succession of updates that followed the v0.3 line.
Notable changes in v0.3.12:
- JSON-RPC now returns standard error objects with numeric error codes, and the command-line JSON-RPC client returns a matching exit code (contributed by Gavin Andresen)
- New
backupwalletRPC command, letting a caller copywallet.datwithout shutting down the node - Various bug fixes and performance improvements
- Network protocol improvements
backupwallet was a modest but practical improvement, not a full fix: a wallet still had to be re-backed-up by hand after every new key. The pre-generated 100-key keypool that actually closed that gap did not ship until v0.3.14 the following month — see the wallet design entry for the full keypool mechanism.
By September 2010 Satoshi was still shipping releases himself, but that same month he had privately told Gavin Andresen he was moving on to other projects — this private notice was the earliest signal of the handover that completed in December.