ORNAX Oppenheimer Rochester High Yield Municipal FD Class A (MM)

Dyer & Berens LLP (www.DyerBerens.com) today announced that it has filed a class action lawsuit in the United States District Court for the District of Colorado on behalf of certain investors of Oppenheimer Rochester National Municipals ("Rochester Fund" or the "Fund") (NASDAQ: ORNAX) (NASDAQ: ORNBX) (NASDAQ: ORNCX) offered by OppenheimerFunds, Inc. ("OppenheimerFunds") who purchased or held shares of the Fund in connection with its November 28, 2005, September 27, 2006, March 9, 2007 and November 28, 2007 offerings (the "Offerings"). The complaint charges OppenheimerFunds, the Rochester Fund and certain of its officers, directors and trustees with violations of federal securities laws.

If you wish to serve as a lead plaintiff, you must move the Court no later than May 12, 2009. If you wish to discuss this action or have any questions concerning this notice or your rights or interests, please contact plaintiff's counsel, Jeffrey A. Berens, Esq. at (888) 300-3362, (303) 861-1764, or via email jeff@dyerberens.com. Any member of the putative class may move the Court to serve as lead plaintiff through counsel of their choice, or may choose to do nothing and remain an absent class member.

The complaint alleges that defendants marketed the Fund as being safer than disclosed in the Offerings while significantly increasing the Fund's leverage exposure and concealing risky investments in inverse floaters, revenue-type municipal securities including tobacco bonds, land secured or "dirt bonds" and airport bonds in hopes of higher returns. Beginning in February 2008, the Fund's shares declined when the auction-rate securities market, which had provided important debt financing for municipal bonds, froze. Defendants continued to conceal the Fund's exposure to these excessively risky investments until the time period between September 2008 and March 2009, when they began to disclose the serious deterioration of the Fund's portfolio. As a result, the Rochester Fund was one of the worst performers in the municipal bond fund market for 2008, losing 49% of its value for the year.

According to the complaint, the true facts which were omitted from the Registration Statements/Prospectuses issued in connection with the Offerings were as follows: (a) the Fund was no longer adhering to its objective of seeking high current income exempt from federal taxation, but in an effort to achieve greater yields was pursuing riskier instruments; (b) the extent of the Fund's liquidity risk due to the illiquid nature of a large portion of the Fund's portfolios, including the Fund's investment in tobacco bonds; (c) the extent to which the Fund's portfolio contained unrated securities; (d) the Fund's internal controls were inadequate to prevent defendants from taking on excessive risk or to prevent them from improperly evaluating the credit quality of unrated securities; (e) the extent of the Fund's risk exposure to derivatives and other high-risk instruments such as inverse floaters was concealed; and (f) the extent of the Fund's leverage exposure was misstated.

Plaintiff seeks to recover damages on behalf of Rochester Fund investors. The plaintiff is represented by Dyer & Berens LLP, which has expertise in prosecuting investor class actions involving financial fraud. The firm's extensive experience in securities litigation, particularly in cases brought under the Private Securities Litigation Reform Act, has contributed to the recovery of hundreds of millions of dollars for aggrieved investors. For more information about the firm, please go to www.DyerBerens.com.

Contact: Jeffrey A. Berens Dyer & Berens LLP 682 Grant Street Denver, CO 80203 Tel: (888) 300-3362 or (303) 861-1764 Email: Email Contact Website: www.DyerBerens.com