Tekelec Recognized as Global Market Share Leader in Signaling by VDC; Worldwide Leadership in SS7 and Growing Sigtran Customer Base Strongly Position Tekelec's 'IMS-Ready' Solutions in Next-Generation Networks.

MORRISVILLE, N.C. & CHICAGO -- Tekelec (NASDAQ: TKLC), a leading developer of high-performance network applications for next-generation fixed, mobile and packet networks, has reaffirmed its global leadership in signaling with its designation as the worldwide market share leader for signaling system 7 (SS7) signal transfer point (STP) shipments by technology market research firm Venture Development Corp. (VDC).

In a recent research report, VDC reported that Tekelec ranked number one globally in 2005 with 38 percent market share for SS7 STP shipments. The closest-ranking competitor had just 18 percent market share.(1)

Tekelec placed first in North America, Central America and Latin America with 61 percent market share, and ranked second in Europe (24 percent) and in Asia-Pacific (26 percent).

"Tekelec's continued market share leadership gives the company a very strong position to support operators around the world as they migrate to IMS (Internet protocol multimedia subsystems) networks using next-generation signaling technologies like Sigtran," said Bob Johnson, senior telecom analyst, VDC.

Sigtran, which enables SS7 signaling over IP networks, is an integral component of Tekelec's "IMS-Ready" solutions, providing a bridge to next-generation architectures while protecting operators' investments in existing network resources. The benefits of Sigtran include increased signaling capacity to reduce network congestion as subscribers adopt new, multimedia services; reduced transport costs by up to 70 percent; and higher network efficiency with fewer administrative costs.

Tekelec is the worldwide leader in Sigtran, with the largest customer network deployment and installations of Tekelec's Sigtran-enabled solutions with leading operators around the globe.

"We are having tremendous success in migrating our extensive installed base of SS7 signaling customers to a next-generation architecture using Sigtran," said Frank Plastina, Tekelec president and CEO. "The VDC report confirms that operators recognize Tekelec's global leadership in network signaling and trust us to guide their transition to the all-IP future with our 'IMS-Ready' solutions."

About Tekelec 'IMS-Ready' Solutions

Tekelec continues to expand its "IMS-Ready" portfolio of products and solutions for the graceful evolution to next-generation networks, which have been deployed widely by operators around the world. The portfolio includes the recently announced Tekelec 3300 Convergence Gateway, TekCore (CSCF), Tekelec 6000 VoIP Application Server, Tekelec 9000 Distributed Switching Solution, Tekelec 7000 Class 5 Packet Switch and Tekelec's comprehensive suite of Integrated Application Solutions (IAS). IAS provides real-time visibility of traffic traversing today's and IMS networks and enables carriers to measure, manage and monetize traffic and services. Tekelec "IMS-Ready" products can be combined to provide complete solutions for Fixed Mobile Convergence, Enhanced VoIP Services and Mobile and Local Hosted Services.

Tekelec is demonstrating its "IMS-Ready" solutions at its GLOBALCOMM booth # 19031, McCormick Place, Chicago, Ill., June 4-8, 2006.

(1) VDC: "2005/2006 Telecom Core Infrastructure Market, Vol. 1, SS7 Network Elements, May 2006"

About Tekelec

Tekelec is a high-performance network applications company that is accelerating the transition to IP Multimedia Subsystem (IMS) networks for service providers around the globe. With its experience at the intersection of network applications and session control, Tekelec creates highly efficient platforms for managing media and delivering network solutions. Corporate headquarters are located near Research Triangle Park in Morrisville, N.C., with research and development facilities and sales offices throughout the world. For more information, please visit www.tekelec.com.