It seems.. by using json backups it's possible to recover lost account names, which is not possible by using exported keys.I can confirm this!
I have a wallet with two accounts and I like to split it into two wallets of one account each. I wish to avoid all the 'unknown name' problem. Any idea how to go about?
1) make a backup of your wallet
2) dump the "owner_key" for the accounts (these give access to the registered name) and store them offline/securly
wallet_dump_account_private_key <name> owner_key
3) dump the "active_key" for access to the funds and trading
wallet_dump_account_private_key <name> active_key
4) import your active_key into an empty wallet
5) regenerate some keys
wallet_regenerate_keys <account> 20000