Aether Systems Joins Phone.com Alliance Program to Provide Enterprise Wireless Data Services; Aether to Serve First WAP Enterprise Customers in February.

Business Editors, High-Tech Writers

OWINGS MILLS, Md.--(BUSINESS WIRE)--Dec. 29, 1999

Aether Systems, Inc. (Nasdaq:AETH), the leading provider of wireless data services for the enterprise, today announced it has joined the Phone.com(TM) (Nasdaq:PHCM) Alliance Program as an applications development member to provide Web-based wireless data services to corporate customers. Aether has developed a Wireless Applications Protocol (WAP) Enterprise Center for its corporate customers and expects to begin offering WAP-enabled services to customers in February 2000.

Aether will leverage Phone.com's expertise in the Internet-enabled mobile phone environment with its own experience in building robust wireless applications for enterprise customers. By combining the complementary services and technologies of the two companies, Aether is further able to provide a complete suite of wireless enterprise services.

"Phone.com is a pioneering force in Web-based phone technologies. They can help us bring the most feature-rich smart-phone capabilities to our enterprise customers," said George Davis, chief operating officer of Aether Systems. "This alliance furthers our goal to offer the most useful applications over the broadest range of devices--including smart phones, handheld computers and two-way pagers--to our enterprise customers."

"We're delighted to be working with Aether Systems," said Kathy Simpson, Director of Developer Marketing for Phone.com. "Enterprise customers are looking for the right partnerships to aid them in developing best-in-class solutions in their industry. By teaming with Phone.com we believe that Aether can provide enterprise customers with excellent WAP-based phone applications and delivery channels."

Aether will use Phone.com's software development tools to develop their smart phone based applications using the Wireless Application Protocol (WAP), a cellular industry standard that allows digital wireless phones to receive data from the Internet. Aether will be able to offer WAP services to its suite of mobile solutions by leveraging the Phone.com's Software Development Kit, UP.SDK(TM). Aether customers will benefit from Phone.com's extensive experience with the complexities of developing applications for a phone's challenging user interface, and from Aether's experience with fault-tolerant robust backend systems as well as wireless development on other small form factor devices.

The new Aether WAP Enterprise Center, to be available in the first quarter of 2000, will help enterprises get the most from WAP technology by offering:

-    An experienced team of wireless data software developers,
     dedicated to creating compelling customized WAP-based
     applications and solutions;

-    The highest level of security and reliability including, hosting
     of enterprise WAP applications on servers inside Aether's network
     operations center;

-    Seamless, private, high speed connections to multiple carriers'
     networks, allowing the broadest possible geographic wireless
     coverage;

-    Aether's full range of end-user customer service, technical
     support and device provisioning capabilities;

-    The ability for end users to also receive content and services
     from a broad array of other devices and networks;

-    Protection from technology obsolescence, as Aether adapts to
     current and future development environments and device operating
     systems for WAP and other protocols.

About Aether

Aether is the leading provider of wireless data services and systems to businesses. Aether's initial focus has been on developing and supporting wireless data applications for leaders in the financial services industry, including stock trading and financial information services for Morgan Stanley/Dean Witter Online, Charles Schwab & Co., Reuters and Bear Stearns. Aether is a member of the WAP Developers' Forum.

For more information, visit Aether's Web site, www.aethersystems.com.

This press release includes forward-looking statements based on our current expectations and projections about future events. These forward-looking statements are subject to a number of risks, uncertainties and assumptions about Aether that could cause actual results to differ materially from those in such forward-looking statements. Potential risks and uncertainties include, but are not limited to, the continued development and customer acceptance of the technology to be licensed by Aether and the ability to offer it on a cost-effective basis. These risks and other risk factors are described in Aether's Form S1/A prospectus under the caption, "Risk Factors" filed pursuant to Rule 424(b) with the Securities and Exchange Commission. Aether undertakes no obligation to update the forward looking statements contained in this press release.

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