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EXHIBIT 23.4
CONSENT OF DONALDSON, LUFKIN & JENRETTE SECURITIES CORPORATION
We hereby consent to (i) the inclusion of our opinion letter, dated
October 26, 2000, to the Board of Directors of Lightbridge, Inc. (the
"Company") as Annex B to the Proxy Statement/Prospectus of the Company
relating to merger of Lightning Merge Corporation, a wholly owned subsidiary
of the Company with and into Corsair Communications, Inc. and (ii) all
references to DLJ in the sections captioned "SUMMARY," "THE MERGER -
Background of the Merger," and "- Opinion of Financial Advisor to
Lightbridge" of the Proxy Statement/Prospectus of the Company which forms a
part of this Registration Statement on Form S-4. In giving such consent, we
do not admit that we come within the category of persons whose consent is
required under, and we do not admit that we are "experts" for purposes of,
the Securities Act of 1933, as amended, and the rules and regulations
promulgated thereunder.
DONALDSON, LUFKIN & JENRETTE
SECURITIES CORPORATION
By: /s/ Adam P. Parten
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Mr. Adam P. Parten
Managing Director
New York, New York
December 22, 2000
