To reproduce:
1. Open an account register.
2. Enter a transaction. For one of the splits, specify an account that doesn't exist yet.
3. Dialog says the account doesn't exist; create it?
4. Say Yes.
5. Second dialog asks the same quesiton.
6. Say no.
7. Create account.

A similar thing happens when creating a new account while selecting a destination account when importing OFX or using online services.

1. Import a file (or get transactions from OFX server).
2. For an imported transaciton, double-click to select an account to use.
3. Click the New Account button.
4. New account window title says (2). Create one account.
5. After clicking ok, a second new account window appears.

This has been around for several versions.