Energy Company Will Be ArcaEx's Second IPO Listing as Exchange Listings Momentum Continues to Grow

CHICAGO and CALGARY, August 4, 2005 - The Archipelago ExchangeSM (ArcaEx®), the nation's first totally open, all-electronic stock exchange, today announced that JMG Exploration, Inc., an independent energy company, has listed on ArcaEx, a facility of the Pacific Exchange, and trading has commenced in its common stock and warrants on ArcaEx. JMG Exploration, Inc., has listed its common stock and warrants exclusively on ArcaEx,. The symbols are: common stock (JMG); $5.00 warrants (JMG+).

In connection with JMG's Initial Public Offering (“IPO”), certain shareholders of JED Oil, Inc. (AMEX:JDO) who live in qualified jurisdictions or met certain regulatory qualifications were entitled to purchase one unit of JMG for every five shares of JED owned as of February 1, 2005 at $5.10 unit. Each unit consists of one share of JMG common stock and a stock purchase warrant entitling the holder to purchase one share of JMG at $5.00 per share. There are now approximately 4.1 million JMG shares outstanding. A registration statement relating to these securities was declared effective by the Securities and Exchange Commission on August 3, 2005.

"We are excited to welcome JMG Exploration to the Archipelago Exchange," said Jerry Putnam, CEO of Archipelago. "We look forward to seeing other innovative and pioneering companies listing exclusively on ArcaEx as we make the listings business more competitive through our new service and new data products."

"As a competitive company in a competitive industry, we have great appreciation for what ArcaEx has brought to the world of stock exchanges," said Scobey Hartley, CEO and President of JMG. "Our decision to IPO and list exclusively on ArcaEx is demonstrative of our commitment to provide our investors with access to an open, fair and efficient trading market."

About JMG Exploration, Inc.
JMG Exploration, Inc. explores for oil and natural gas in the United States and Canada. The Company has completed two private placements totaling $8.8 million in August 2004 and has commenced exploration activities. To date JMG Exploration, Inc. has entered into:

• A farm-in agreement for a prospect in the Powder River Basin area of eastern Wyoming, which the Company refers to as the Hooligan Draw prospect;
• An exploration, development and conveyance agreement with Fellows Energy Ltd. to drill its Weston County, Wyoming and Gordon Creek, Utah prospects, as amended to terminate JMG Exploration, Inc.'s drilling and expenditure commitments;
• A farm-in agreement and direct purchase of acreage for several prospects in the Bakken Zone of North Dakota which the Company refers to as the Candak prospect, Myrtle Beach prospect and Bluffton prospect;
• A 77.5% interest in a section of land in the Pinedale anticline field in Wyoming referred to as the Pinedale anticline prospect;
• A farm-in agreement for a prospect in the Cut Bank Sand field of Montana, which JMG Exploration, Inc. refer to as the Cut Bank prospect and which was terminated during the quarter ended December 31, 2004; and,
• A farm-in agreement for a prospect in the Fiddler Creek Heavy Oil District in southern Montana, which the Company refers to as the Fiddler Creek prospect. JMG Exploration, Inc. has since re-evaluated the Fiddler Creek prospect and has recently terminated the agreement.

Use of Proceeds by JMG Exploration, Inc.
JMG Exploration, Inc. intends to use the net proceeds of this offering of approximately $8,800,850 for the development of oil and gas exploration prospects. The Company will receive additional net proceeds of up to $1,402,627, if JMG Exploration, Inc.'s underwriter, Gilford Securities Incorporated, exercises its overallotment option to purchase up to 285,000 additional units, for total combined net proceeds of $10,203,477.

About ArcaEx
Archipelago Holdings (PCX: AX) operates The Archipelago Exchange SM (ArcaEx®) the first totally open all-electronic stock exchange in the United States. ArcaEx trades all Nasdaq-listed equity securities and exchange listed equity securities, including those listed on the New York Stock Exchange®, American Stock Exchange®, and Pacific Exchange®. In addition to offering core execution services, ArcaEx provides corporate clients with listing services and innovative data products. In 2004, Archipelago launched ArcaVision to provide corporate and trading clients with more transparent market data, analytical tools and access to market-wide and ArcaEx specific trading information. Archipelago Holdings completed its initial public offering in August 2004. For more information please visit http://www.arcaex.com. ArcaEx operates three single-price auctions each trading day.

Currently over 230 companies are listed on ArcaEx, a facility of the Pacific Exchange. In addition to its own listings, the exchange trades all NYSE-, Nasdaq-, and Amex-listed stocks. The JMG IPO follows ArcaEx's highly successfully IPO and listing of its parent company, Archipelago Holdings, Inc. and marks the second time a company has listed exclusively on ArcaEx.

This news release shall not constitute an offer to sell or a solicitation of an offer to buy, nor shall there be any sale of these securities in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

Forward Looking Statements for JMG Exploration, Inc. "Safe Harbor" statement under the Private Securities Litigation Reform Act of 1995: This news release contains forward-looking statements that are subject to risk and uncertainties, including, but not limited to, the impact of competitive services, demand for services like those provided by the company and market acceptance risks, fluctuations in operating results, cyclical market pressures on the oil and natural gas industry and other risks detailed from time to time in the company's filings with Securities and Exchange Commission. JMG Exploration, Inc. undertakes no obligation to update or revise any forward-looking statements whether as a result of new developments or otherwise.

Forward-Looking Statements for Archipelago Certain statements in this press release may contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These statements are based on Archipelago's current expectations and involve risks and uncertainties that could cause Archipelago's actual results to differ materially from those set forth in the statements. There can be no assurance that such expectations will prove to be correct. Factors that could cause Archipelago's results to differ materially from current expectations include: general economic and business conditions, industry trends, competitive conditions, regulatory developments as well as other risks or factors identified in the Company's filings with the Securities Exchange Commission, including its Report on Form 10-K for the fiscal year ending December 31, 2004 which is available on the Company's website at http://www.archipelago.com. You should not place undue reliance on forward-looking statements, which speak only as of the date of this press release. Except for any obligation to disclose material information under the Federal securities laws, Archipelago undertakes no obligation to release publicly any revisions to any forward-looking statements to reflect events or circumstances after the date of this press release.

Contact:
Archipelago
Margaret Nagle
312-442-7083

Company Contacts
JMG Exploration, Inc.
Joanne Finnerty, CFO
(403) 537-3250
H.S. (Scobey) Hartley, CEO & President
(403) 261-2959

Investor Relations Counsel
The Equity Group Inc.
Linda Latman (212) 836-9609
Andreas Marathovouniotis (212) 836-9611
www.theequitygroup.com