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EXHIBIT 5.1
KELLEY DRYE & WARREN LLP
Two Stamford Plaza
281 Tresser Boulevard
Stamford, Connecticut 06901
(203) 324-1400
January 16, 2001
Board of Directors
Nx Networks, Inc.
13595 Dulles Technology Drive
Herndon, VA 20171
Ladies and Gentlemen:
We have acted as counsel to Nx Networks, Inc., a Delaware
corporation (the "Company"), in connection with a Registration Statement on Form
S-8 (the "Registration Statement") relating to the Company's registration under
the Securities Act of 1933, as amended (the "Act"), of 1,799,714 shares (the
"Shares") of the Company's common stock, par value $.05 per share, that will be
issuable upon the exercise of stock options granted or to be granted pursuant to
the Amended and Restated AetherWorks Corporation 1997 Stock Option Plan (the
"Plan").
We have examined such documents and have reviewed such matters
of law deemed necessary by us in order to deliver the within opinion. In the
course of such examination and review, we have assumed the genuineness of all
signatures, the authority of all signatories to sign on behalf of their
principals, if any, the authenticity of all documents submitted to us as
original documents and the conformity to original documents of all documents
submitted to us as certified or photostatic copies. As to certain factual
matters, we have relied upon information furnished to us by officers of the
Company.
Based on the foregoing and solely in reliance thereon, it is
our opinion that the Shares have been duly authorized and, upon issuance,
delivery and payment therefor in accordance with the terms of the Plan, will be
validly issued, fully paid and nonassessable.
We hereby consent to the filing of this letter as an exhibit
to the Registration Statement, and to all references to our firm included in the
Registration Statement, as of the date hereof. In giving such consent, we do not
admit that we are in the category of persons whose consent is required under
Section 7 of the Act or the rules and regulations promulgated thereunder.
Very truly yours,
KELLEY DRYE & WARREN
By: /s/ M. Ridgway Barker
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A Member of the Firm
