EX 99.1

                        TEKELEC ACQUIRES VOCALDATA, INC.

   ACQUISITION BROADENS TEKELEC'S NEXT-GENERATION SWITCHING PRODUCT PORTFOLIO

CALABASAS, CA (MONDAY, SEPTEMBER 20, 2004): Tekelec (NASDAQ: TKLC) today
announced that it has acquired VocalData, Inc., a provider of hosted Internet
protocol (IP) telephony applications that enable the delivery of advanced
telecom services and applications to business and residential customers. With
the acquisition, Tekelec, a global supplier of telecommunications products for
next-generation fixed, mobile and packet networks, enables operators to deliver
time division multiplex (TDM) and IP services such as IP Centrex, hosted PBX
services and voice virtual private networking (VPN) as they migrate to
next-generation networks.

Tekelec purchased 100 percent of VocalData's outstanding stock for approximately
$27.5 million, consisting of $14.5 million of cash and approximately 780,000
shares of Tekelec common stock, or $13.0 million, based on today's closing
price. VocalData will be integrated into Tekelec's Next-Generation Switching
business unit.

VocalData, headquartered in Richardson, Texas, is a North American market share
leader in IP Centrex, accounting for 44 percent of all IP Centrex lines deployed
at the end of 2003, based on 2003 IP Centrex NA line shipments reported in a
recent Frost & Sullivan study. Globally, VocalData has an estimated 34 percent
share of all IP Centrex lines shipped, according to iLocus' 5th Annual Industry
Update on the Global VoIP Market 2004.

Tekelec will leverage VocalData's hosted IP telephony application server to
provide an immediate path to IP service delivery and profitability for wireless,
wireline and cable operators and their subscribers. The VocalData products will
complement Tekelec's next-generation switching product portfolio to enable
advanced features such as integration with Outlook and Instant Messenger, IP
Centrex with flexible call routing and treatment via customer web portals and
find me/follow me capabilities.

In addition, Tekelec will offer VocalData's products and solutions as
stand-alone applications to deliver advanced VoIP service options like IP PBX
for legacy PBX replacement and Internet-based voice services to enterprise WAN
and private VPN services.

Finally, when integrated in Tekelec's EAGLE(R) 5 Signaling Application System,
VocalData's solutions will provide added capabilities to deliver enhanced
business and consumer voice services across circuit and packet-based networks,
such as customer Web portals for feature activation across traditional phone
lines.

"The acquisition uniquely positions Tekelec to address customers' network-wide
application requirements for today's circuit-switched and tomorrow's
next-generation networks," said Fred Lax, Tekelec's president and CEO.
"Combining VocalData's application server with our next-generation switching
portfolio supports our commitment to offer solutions that enable service
providers to deliver revenue-generating services today, allowing them to
flexibly transform their networks. Operators can begin deploying VoIP features
quickly and reliably, while controlling capital expenditures and consistently
lowering operating expenses."

VocalData's open standards approach and support of all key IP end point
protocols, including session initiation protocol (SIP), media gateway control
protocol (MGCP), simple client control protocol (SCCP) and MiNet IP protocol,
enable carriers to create and customize their own services and deliver the
broadest choice in end-user equipment. The company's highly scalable
architecture supports over 700,000 busy hour call attempts, or the equivalent of
200 calls per second, and also allows for firewall traversal, eliminating the
need for additional hardware or software at the enterprise or central office.

Lax added, "VocalData's global customer base and experience in service provider
networks worldwide further enables our global expansion. Its products carry
revenue-generating traffic in live networks of more than 50 operators around the
globe, including NTT, Telus and ICG, in addition to business customers through
leading systems integrators.



"Tekelec and VocalData have collaborated on deployments globally and
demonstrated product interoperability in many commercial installations,"
concluded Lax. "Our complementary products and shared expertise provide a strong
foundation for the future success of our combined solutions portfolio."

Tekelec expects the transaction to have no impact on its third quarter results,
excluding any potential non-cash, in-process research and development charge. On
a GAAP basis, Tekelec expects the transaction to reduce its Q4 2004 EPS by
approximately $0.01 to $0.03. Tekelec expects the Q4 2004 earnings reduction to
include amortization of acquired intangibles and the amortization of deferred
compensation totaling approximately $250,000, pretax. For 2005, on a GAAP basis,
Tekelec expects the transaction to reduce its EPS by approximately $0.03 to
$0.05. Tekelec expects the 2005 earnings reduction to include amortization of
acquired intangibles and the amortization of deferred compensation totaling
approximately $1.0 million, pretax. Tekelec expects the transaction to be
accretive to earnings in 2006.

For fiscal year 2003, VocalData revenues were approximately $4.8 million, with
gross margins of approximately 70 percent. Operating expenses were approximately
$3.5 million per quarter.

Employment Inducement Stock Options and Restricted Stock Units

In connection with the acquisition, 69 VocalData officers and employees were
granted employment inducement stock options to purchase a total of 1,083,400
shares of Tekelec common stock, pursuant to NASDAQ Marketplace Rule 4350 (i) (1)
(A) (iv). The number of shares involved in these grants amounts to less than 2%
of the outstanding common shares of Tekelec. All option grants have an exercise
price equal to Tekelec's closing price on September 20, 2004, and will vest over
a four-year period.

In addition, eight VocalData officers and key employees were granted Restricted
Stock Units (RSUs) totaling 18,000 shares of Tekelec common stock, pursuant to
NASDAQ Marketplace Rule 4350 (i) (1) (A) (iv). The RSUs will vest one year from
the grant date.

About Tekelec

Tekelec is a leading developer of now and next-generation signaling and
switching telecommunications solutions, network monitoring technology, and
value-added applications. Tekelec's innovative solutions are widely deployed in
traditional and next-generation wireline and wireless networks and contact
centers worldwide. Corporate headquarters are located in Calabasas, California,
with research and development facilities and sales offices throughout the world.
For more information, please visit www.tekelec.com.

About VocalData

VocalData, Inc. provides an integrated suite of hosted IP telephony applications
that enable service providers to reliably and cost-effectively deliver
voice-over-IP solutions. VocalData's award-winning application server is an open
solution that allows service providers to deliver higher value telephony
services to business and residential customers. Through its more than 50
customers and broad partner base, VocalData supports more than 225,000 deployed
enhanced IP telephony lines today. VocalData was founded in 1998 and is
headquartered in Richardson, Texas. For more information, visit
www.vocaldata.com.

                                      # # #

The Tekelec logo, EAGLE, G-Flex, G-Port, and IP7 are registered trademarks of
Tekelec. Sentinel, TekServer, and TekWare are trademarks of Tekelec. All other
trademarks are the property of their respective owners.



Forward-Looking Statements

Certain statements made in this news release are forward looking, reflect the
Company's current intent, belief or expectations and involve certain risks and
uncertainties. There can be no assurance that the Company's actual future
performance will meet the Company's expectations. As discussed in the Company's
2003 Annual Report on Form 10-K and other filings with the SEC, the Company's
future operating results are difficult to predict and subject to significant
risks and fluctuations. Factors that may cause future results to fluctuate or
differ materially from the Company's current expectations include, among others:
overall telecommunications spending, changes in general economic conditions, the
timing of significant orders and shipments, the lengthy sales cycle for the
Company's products, the timing of the convergence of voice and data networks,
the success or failure of strategic alliances or acquisitions including the
success or failure of the integration of Santera and Taqua's operations with
those of the Company, the ability of carriers to utilize excess capacity of
signaling infrastructure and related products in their networks, the capital
spending patterns of customers, the dependence on wireless customers for a
significant percentage and growth of the Company's revenues, the timely
development and introduction of new products and services, product mix, the
geographic mix of the Company's revenues and the associated impact on gross
margins, market acceptance of new products and technologies, carrier deployment
of intelligent network services, the ability of our customers to obtain
financing, the level and timing of research and development expenditures,
regulatory changes, and the expansion of the Company's marketing and support
organizations, both domestically and internationally. The Company undertakes no
obligation to publicly update any forward-looking statements whether as a result
of new information, future events or otherwise.

Investor Contacts:
Mike Attar
Director, Investor Relations, Tekelec
818.880.7821
michael.attar@tekelec.com

U.S. Press Contact:
Joni K. Brooks
Manager, Public Relations, Tekelec
919-461-1065
Joni.Brooks@Tekelec.com