How to prevent sending an unbalanced Manual Journal for Approval in Oracle E-Business General Ledger

How can I prevent through personalization or profile submission of unbalanced journal for approval. We are using encumbrance, so don't want the user to check or reserve fund for an unbalanced journal. In addition, he should not be able to submit such journal for approval.

However, he can save such unbalanced journal and can continue the journal later. But as long as the journal credit and debit is not balanced, the user should not check for fund or reserve or send for approval until the journal lines are balanced.