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                                                                  EXHIBIT 10.16


                                                     [LUCENT TECHNOLOGIES LOGO]



September 14, 2000



Jack Ingram
XETA Technologies, Inc.
1814 W. Tacoma
Broken Arrow, OK  74012


RE: NOTICE OF ASSIGNMENT

As you know, Lucent Technologies Inc. ("Lucent") announced on March 1, 2000
plans to spin off its PBX, SYSTIMAX(R) structured cabling and LAN-based data
business (collectively referred to as "Enterprise Networks Group") to
shareowners, forming a separate company that will focus directly and
independently on the enterprise networking market.* The new company known as
Avaya Inc., will commence operations with revenues of approximately $8 billion
per year and a customer list that includes more than ninety percent of the
Fortune 500 companies. Avaya will be a wholly owned subsidiary of Lucent
immediately prior to the spin-off which is expected to occur on October 1, 2000.

The purpose of this letter is to provide formal notice that all contracts and
agreements previously entered into between your company and Lucent for products
and services from the Enterprise Networks Group are assigned from Lucent to
Avaya, effective immediately prior to the spin-off on October 1, 2000.

Though our name has changed, we continue to be committed to serving our global
markets and to providing the same quality products and customer service with the
same professionalism and integrity you have come to know and expect.

All of us at Avaya look forward to serving your communication networking needs
as we move forward as an exciting, fully independent business.


/s/ JAN BURTON


Jan Burton
National Sales Vice President

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*The Enterprise Networks Group's PBX and voice messaging businesses were
included in Lucent's former Business Communications Systems business unit. The
SYSTIMAX(R) business was formerly included in Lucent's Network Systems business
unit.