Does error within transaction imply restarting it?

Hello dear fellows,

I need to get insight about this:

1. A transaction begins
2. LOCK TABLE XYZ; is issued.
3. Since table XYZ doesn't exist, the backend gives error.
4. A CREATE TABLE XYZ(field char); is issued.
5. The backend says that it is in abort state, and that all queries will
be ignored until commit, or end of transaction.

Is this behaviour unavoidable? I mean, can the backend ignore the fact
that I issued a command that yielded an error, and continue accepting
SQL statements within the transaction? Is there a hack or something?

Thank you very much in advance.

Cheers,
Haroldo.