Oakland, CA — April 2, 2009 — Zhone Technologies, Inc. (NASDAQ: ZHNE), a global leader in multi-service access solutions, today announced preliminary estimates for the first quarter of 2009. Based on preliminary information, revenue for the first quarter 2009 is expected to be approximately $24 million, more than the slight decline anticipated from fourth quarter 2008 revenue of $31 million. Despite the anticipated lower revenue level, gross margins are expected to be between 31% and 33%, in line with previously provided guidance. Proforma operating expenses are also expected to be in line with previously provided guidance of between $14 million to $15 million.

Zhone's chief executive officer Mory Ejabat stated, "The first quarter of 2009 is normally a seasonally weak quarter but proved to be even more challenging with the global economic difficulties. We're encouraged, however, by growing backlog and prospects for revenue growth throughout the remainder of the year."

These results are preliminary, and therefore, subject to the company's completion of its customary quarterly closing and review procedures. Zhone is scheduled to release its final first quarter results on Thursday, April 23, 2009, after the close of regular market trading.

Zhone will conduct a conference call and audio webcast to discuss further details of its first quarter 2009 results at approximately 2:00 p.m. PT / 5:00 p.m. ET on Thursday, April 23, 2009. This call is open to the public by dialing +1 (800) 237-9752 for U.S. callers and +1 (617) 847-8706 for international callers and then entering passcode 51358333. The audio webcast will be simultaneously available on the Investor Relations section of Zhone's website at http://www.zhone.com/investors/.

A replay of the conference call will be available after the original call by dialing +1 (888) 286-8010 for U.S. callers and +1 (617) 801-6888 for international callers and then entering passcode 48028058. An audio webcast replay will also be available online at http://www.zhone.com/investors/ for approximately one week following the original call.

About Zhone Technologies - Access for a Converging World

Zhone Technologies, Inc. (NASDAQ: ZHNE) is a global leader in multi-service access network (MSAN) solutions, serving more than 700 of the world's most innovative network operators. The company offers the industry's only fully-integrated portfolio of MSAP, FTTx, EFM and Wi-Fi access technologies, enabling a full suite of services, including residential and business broadband, VoIP, and High-Definition IPTV. Zhone's converged multi-service access platform helps operators rapidly deploy premium services using copper, fiber, and wireless while improving network agility and reducing costs. Based in the United States, Zhone is the only vendor in the field whose MSAN platforms are all manufactured in the USA, and our facilities are emission, waste-water and CFC free. www.zhone.com

Contacts:

Investors
Tel: +1 510-777-7013
Fax: +1 510-777-7001
Email: investor-relations@zhone.com Media
Tel : +1 510-777-7020
Fax : +1 510-777-7001
Email: public-relations@zhone.com

Zhone, the Zhone logo, and all Zhone product names are trademarks of Zhone Technologies, Inc. Other brand and product names are trademarks of their respective holders. Specifications, products, and/or product names are all subject to change without notice.

Zhone's Single Line Multi-Service architecture (SLMS™), allows carriers to concurrently deliver voice, new premium data and video services over copper or fiber access lines.