The Public Company Accounting Oversight Board voted unanimously to circulate the proposal for public comment. The proposal would require auditors to include an explanatory paragraph in a report outlining whether a restatement reflected a change in an accounting principle or an error correction, according to Keith Wilson, PCAOB's associate chief auditor.

"This is really intended to be an alert," he said at a board meeting.

Before the proposal becomes a rule, it must be approved by the PCAOB and the Securities and Exchange Commission.

The board separately agreed to a second delay of part of a rule designed to ensure that auditor independence wasn't compromised by providing tax services to an audit client's executives. The rule went into effect in October 2006, but the board later delayed a portion of the rule until April 30, 2007, and on Tuesday approved another delay until July 31, 2007.

The rule at issue prevents auditing firms from conducting public-company audits in the same year that they have provided tax services for executives at the company who have an oversight role in the preparation of the company's financial reports. Under the delay, the rule won't apply to tax services provided on or before July 31 when services provided during the audit period are completed before the professional engagement begins, the board said.

In delaying the application of the rule, the board voted to seek public comment for 45 days on whether an accounting firm that has provided such tax services should be able to accept an assignment as the company's auditor later the same year.