New Video Phone Service Connects 5tel Communications
   Customers in Australia With Family and Friends Worldwide Like
                           Never Before

NEW YORK, May 25, 2010 (GLOBE NEWSWIRE) -- deltathree, Inc.
(OTCBB:DDDC), a global provider of integrated video and Voice over
Internet Protocol (VoIP) telephony services, products, hosted turnkey
solutions and infrastructures for service providers, resellers and
direct consumers, today announced it has secured a new service provider
contract with 5tel Communications Pty Ltd, an Australian-based Internet
telephony company. deltathree will supply the digital phone and video
phone service for 5tel's move into the Australian video phone market,
which is targeted to go live during the current quarter, as well as a
full spectrum of service provider back-end support services, including
network management, billing, provisioning, eCommerce and custom web and
application development. The launch is driven by the solid
opportunities 5tel sees for growth in the video phone market as well as
the attraction of an integrated offering with the current 5tel IP phone
service.

Douglas Archbold, 5tel's General Manager, stated, "5tel's philosophy is
to stay ahead of the communications market with the development and
deployment of next generation digital video and phone solutions. Our
new 5tel video phone service, supported by deltathree, aims to bring
social networks, family and friends closer together. We deliver an
immediate video connection, offering a new way to experience
interactive communications, allowing family members that may be
separated by vast distances, or challenges such as the hearing
impaired, to enjoy a face-to-face conversation in real-time, anytime.
The 5tel 'plug in and play' Yealink VP2009P Videophone connects to a
customer's existing broadband DSL or cable Internet connection and
produces excellent, consistent video quality."

Mr. Effi Baruch, interim Chief Executive Officer and President, and
Senior Vice President of Operations and Technology of deltathree,
commented on the new agreement, "With the current market for video
phone services largely under-penetrated on a global basis, and with the
widespread availability of quality high speed Internet to global
consumers and small businesses, we see a vast potential market to
leverage our world-class international VoIP and video-over-IP network.
Our turnkey communication services offer our valued service provider
clients such as 5tel leading edge technology solutions to help them
extend their innovative vision worldwide."

About 5tel Communications Pty Ltd

5tel Communications Pty Ltd is a leading Australian internet telephony
company, with a presence in Melbourne, Sydney, Canberra, Adelaide and
the Gold Coast. The company operates in five distinct divisions,
including IP Pbx; video voice and video phone; IP smart mobile;
international sim; and One World roaming sim (which reaches over 200
countries worldwide, with free incoming calls in over 80 countries) and
serves as one of Australia's largest IP payphone systems offering
consumers a reduction of up to 98% in call costs while providing media
streaming. The company began operations as OzVOIP in 2004, specializing
in the sale and installation of business phone systems using internet
telephony technology (IP PABX's and payphones), and was the first to
launch coin-operated internet telephony payphones. For more information
about 5tel please visit: www.5tel.com.au

About deltathree

Founded in 1996, deltathree, Inc. is a global provider of integrated
video and Voice over Internet Protocol (VoIP) telephony services,
products, hosted turnkey solutions and infrastructures for service
providers, resellers and direct consumers. Supporting tens of thousands
of active users around the world, deltathree serves customers through
its two primary distribution channels: the service provider and
reseller channel and the direct-to-consumer channel. deltathree's
advanced solutions offer service providers and resellers a full
spectrum of private label IP-based digital voice and video products and
services, as well as a back-office suite of services. Utilizing
advanced Session Initiation Protocol (SIP) technology, deltathree
provides all the components to support a complete VoIP service
deployment. deltathree's direct-to-consumer channel consists of the
iConnectHere direct-to-consumer offering and joip, which powers the
VoIP service of Panasonic's Globarange hybrid phone.

For more information about deltathree please visit: www.deltathree.com.

Except for historical matters contained herein, the matters discussed
in this press release are forward-looking and are made pursuant to the
safe harbor provisions of the Private Securities Litigation Reform Act
of 1995. Investors are cautioned that these forward-looking statements
reflect numerous assumptions and involve risks and uncertainties that
may affect deltathree's business and prospects and cause actual results
to differ materially from these forward-looking statements. Among the
factors that could cause actual results to differ are: our ability to
obtain additional capital in the near-term to finance operations; our
ability to reduce our costs and expenses and expand our revenues; our
ability to retain key personnel and employees needed to support our
services and ongoing operations; our dependence on a small number of
key customers for a significant percentage of our revenue ; decreasing
rates of telecommunications services; the public's acceptance of VoIP
telephony, and the level and rate of customer acceptance of our new
products and services; the competitive environment of Internet
telephony and our ability to compete effectively; fluctuations in our
quarterly financial results; our ability to maintain and operate our
computer and communications systems without interruptions or security
breaches; our ability to operate in international markets; our ability
to provide quality and reliable service, which is in part dependent
upon the proper functioning of equipment owned and operated by third
parties; the uncertainty of future governmental regulation; our ability
to protect our intellectual property against infringement by others,
and the costs and diversion of resources relating to any claims that we
infringe the intellectual property rights of third parties; our ability
to comply with governmental regulations applicable to our business; the
need for ongoing product and service development in an environment of
rapid technological change; and other risks referenced from time to
time in our filings with the SEC and available on the Internet at
http://www.sec.gov. Except as required under the federal securities
laws and the rules and regulations of the SEC, deltathree does not have
any intention or obligation to update publicly any forward-looking
statements after the distribution of this news release, whether as a
result of new information, future events, changes in assumptions or
otherwise.


CONTACT:  Grayling
          Investor Relations Contact:
          Erik Knettel
          1-646-284-9415
          ir@deltathree.com

          deltathree, Inc.
          Ziv Zviel, Chief Financial Officer and Treasurer
          1-212-500-4860
          ziv.zviel@deltathree.com