Spirent Communications PLC announces - Director/PDMR Shareholding


Crawley, UK -- (MARKET WIRE) -- December 21, 2006 --


                         SPIRENT COMMUNICATIONS PLC

                                  (the "Company")

                        NOTIFICATION OF DEEMED INTERESTS
                  BY DIRECTORS, PERSONS DISCHARGING MANAGERIAL
                       RESPONSIBILITY OR CONNECTED PERSONS



The Company was notified on 21 December 2006 that Spirent Sharesave Trust
Limited, the trustee for the Spirent Sharesave Trust (the "Trust") had
transferred Ordinary shares to satisfy the exercise of options under the
Company's Savings Related Share Option Scheme as follows:



No of Shares            Option Price

9,710                     38 pence



Following this transfer the total number of Ordinary shares held by the Trust
is:


1,857,576 (representing 0.21% of the issued share capital of the Company).


The Company's executive directors are potential beneficiaries of the Trust
(together with all other UK employee share option holders) and are, therefore,
treated under the Companies Act 1985 as having a deemed interest in the total
number of shares held by the Trust.  As a result, the directors' deemed interest
in the Trust has been reduced by the above number of shares transferred.



For the avoidance of doubt, the Company confirms that this notification does not
relate to an actual dealing in securities by the executive directors whose
interests in the Company's securities remain unchanged notwithstanding the above
events.





Warren Nash
Spirent Communications plc


                      This information is provided by RNS
            The company news service from the London Stock Exchange
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