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                                                                     EXHIBIT 4.6


                          REGISTRATION RIGHTS AGREEMENT



         THIS REGISTRATION RIGHTS AGREEMENT (the "AGREEMENT") is
made and entered into as of August 6, 2001 by and among Lucent Technologies
Inc., a Delaware corporation (the "COMPANY"), Salomon Smith Barney Inc.
("SALOMON SMITH BARNEY"), Morgan Stanley & Co. Incorporated ("MORGAN
STANLEY"), Bear, Stearns & Co.,  J.P. Morgan Securities Inc., Merrill Lynch,
Pierce, Fenner & Smith Incorporated and SG Cowen Securities Corporation
(collectively, the "INITIAL PURCHASERS"), for whom Salomon Smith Barney Inc.
and Morgan Stanley & Co. Incorporated are acting as representatives (the
"REPRESENTATIVES").

         This Agreement is made pursuant to the Purchase Agreement dated August
1, 2001, among the Company and the Initial Purchasers (the "PURCHASE
AGREEMENT"), which provides for the sale by the Company to the Initial
Purchasers of up to 1,885,000 shares (including up to 135,000 shares that the
Company has granted the Initial Purchasers an option to purchase pursuant to the
Purchase Agreement) of its 8.00% Redeemable Convertible Preferred Stock, par
value $1.00 per share and initial liquidation preference $1,000.00 (the
"PREFERRED STOCK"). The Preferred Stock will be convertible into shares of
Common Stock, par value $.01 per share, of the Company (the "COMMON STOCK") at
the conversion price set forth in the Final Memorandum (as defined in the
Purchase Agreement), and exchangeable at the Company's option for convertible
subordinated debentures (the "CONVERTIBLE DEBENTURES") to be issued, if and when
issued, pursuant to an indenture a form of which is attached to the Certificate
of Designations of the Preferred Stock. For purposes of this Agreement, the term
"SECURITIES" refers to the Preferred Stock, any Convertible Debentures issued in
exchange for Preferred Stock and all shares of Common Stock issued on conversion
thereof.

         In order to induce the Initial Purchasers to enter into the Purchase
Agreement, the Company has agreed to provide to the Initial Purchasers and their
direct and indirect transferees the registration rights with respect to the
Securities set forth in this Agreement. The execution of this Agreement is a
condition to the closing under the Purchase Agreement.

         In consideration of the foregoing, the parties hereto agree as follows:
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         1. Definitions.

         As used in this Agreement, the following capitalized defined terms
shall have the following meanings:

         "ADDITIONAL DIVIDENDS" shall have the meaning set forth in the
Certificate of Designations.

         "ADDITIONAL INTEREST" shall have the meaning set forth in the
Indenture.

         "1933 ACT" shall mean the Securities Act of 1933, as amended from time
to time.

         "1934 ACT" shall mean the Securities Exchange Act of 1934, as amended
from time to time.

         "CERTIFICATE OF DESIGNATIONS" shall mean the Certificate of
Designations relating to the Preferred Stock, which sets forth the powers,
preferences and rights, and the qualifications, limitations and restrictions of
the Preferred Stock.

         "CLOSING DATE" shall mean the Closing Date as defined in the Purchase
Agreement.

         "COMMON STOCK" shall have the meaning set forth in the preamble.

         "COMPANY" shall have the meaning set forth in the preamble and shall
also include the Company's successors.

         "CONVERTIBLE DEBENTURES" shall have the meaning set forth in the
preamble.

         "HOLDERS" shall mean the Initial Purchasers, for so long as they own
any Registrable Securities (except that for purposes of Section 4 hereof, the
Initial Purchasers shall always be considered Holders), and each of their
respective successors, assigns and direct and indirect transferees who become
registered owners of Registrable Securities.

         "INITIAL PURCHASERS" shall have the meaning set forth in the preamble.

         "INDENTURE" shall mean the Indenture relating to the Company's 8.00%
Convertible Subordinated Debentures due 2031, issuable upon exchange for the
Preferred Stock, which sets for the powers, preferences, rights, qualifications,
limitations and restrictions of the Convertible Debentures.

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         "MAJORITY HOLDERS" shall mean the Holders of a majority of the
aggregate principal amount of outstanding Registrable Securities; provided that,
for purposes of Section 5(b), whenever the consent or approval of Holders of a
specified percentage of Registrable Securities is required hereunder,
Registrable Securities held by the Company or any of its affiliates (as such
term is defined in Rule 405 under the 1933 Act) (other than the Initial
Purchasers or subsequent Holders of Registrable Securities if such subsequent
holders are deemed to be such affiliates solely by reason of their holding such
Registrable Securities) shall not be counted in determining whether such consent
or approval was given by the Holders of such required percentage or amount.

         "PERSON" shall mean an individual, partnership, limited liability
company, corporation, trust or unincorporated organization, or a government or
agency or political subdivision thereof.

         "PREFERRED STOCK" shall have the meaning set forth in the preamble.

         "PURCHASE AGREEMENT" shall have the meaning set forth in the preamble.

         "PROSPECTUS" shall mean the prospectus included in a Shelf Registration
Statement, including any preliminary prospectus, at the time such Registration
Statement is declared effective, and any such prospectus as amended or
supplemented by any prospectus supplement, including a prospectus supplement
with respect to the terms of the offering of any portion of the Registrable
Securities covered by a Shelf Registration Statement, and by all other
amendments and supplements to such prospectus, and in each case, including all
material incorporated by reference therein.

         "REGISTRABLE SECURITIES" shall mean the Securities; provided, however,
that the Securities shall cease to be Registrable Securities on the earlier to
occur of (i) the date on which a Shelf Registration Statement with respect to
such Securities shall have been declared effective under the 1933 Act and such
Securities shall have been disposed of pursuant to such Shelf Registration
Statement, (ii) the date on which such Securities may be sold to the public
pursuant to Rule 144(k) (or any similar provision then in force, but not Rule
144A) under the 1933 Act or (iii) the date on which such Securities shall have
ceased to be outstanding.

         "REGISTRATION DEFAULTS" shall mean the occurrence of any of the
following events:

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         (i)      on or prior to the 180th day following the date of original
                  issuance of the Preferred Stock, a Shelf Registration
                  Statement has not been filed with the SEC,

         (ii)     on or prior to the 210th day following the date of original
                  issuance of the Preferred Stock, a Shelf Registration
                  Statement has not been declared effective by the SEC or

         (iii)    after a Shelf Registration Statement has been declared
                  effective by the SEC, the Shelf Registration Statement
                  thereafter ceases to remain effective or useable (except as
                  provided in the second to last paragraph of Section 3) in
                  connection with resales of the Registrable Securities during
                  the period specified in the third sentence of Section 2(a);

provided, however, that a Registration Default shall cease to occur and be cured
under clause (i) above at such time as the Shelf Registration Statement is
filed; under clause (ii) above at such time as the Shelf Registration Statement
is declared effective by the SEC; and under clause (iii) above at such time as
the Shelf Registration Statement becomes effective or usable again after ceasing
to be effective or usable.

         "REGISTRATION EXPENSES" shall mean any and all expenses incident to
performance of or compliance by the Company with this Agreement, including
without limitation: (i) all SEC, stock exchange or National Association of
Securities Dealers, Inc. registration and filing fees, (ii) all fees and
expenses incurred in connection with compliance with state securities or blue
sky laws (including reasonable fees and disbursements of counsel (not to exceed
$10,000) for any underwriters or Holders in connection with blue sky
qualification of any of the Registrable Securities), (iii) all expenses of
printing and distributing, at the request of the Company, any Shelf Registration
Statement, any Prospectus, any amendments or supplements thereto, (iv) all
rating agency fees, (v) all fees and disbursements of the Transfer Agent, (vi)
the fees and disbursements of counsel for the Company and the reasonable fees
and disbursements of one counsel for the Holders incurred on or before the
initial effectiveness of the Shelf Registration Statement, which counsel shall
be counsel for the Initial Purchasers or other counsel selected by the Majority
Holders and satisfactory to the Company ("COUNSEL FOR THE HOLDERS"), (vii) the
fees and disbursements of the independent public accountants of the Company,
including the expenses of any special audits or "cold comfort" letters required
by or incident to such performance and compliance, and (viii) the fees and
expenses of listing the Common Stock on any securities exchange or quotation
system in accordance with Section 3(o) hereof,

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but excluding underwriting discounts, if any, and commissions and transfer
taxes, if any, relating to the sale or disposition of Registrable Securities by
the Holders.

         "SEC" shall mean the Securities and Exchange Commission.

         "SECURITIES" shall have the meaning set forth in the preamble.

         "SHELF REGISTRATION" shall mean a registration effected pursuant to
Section 2(a) hereof.

         "SHELF REGISTRATION STATEMENT" shall mean a "shelf" registration
statement of the Company pursuant to the provisions of Section 2(a) of this
Agreement which covers all of the Registrable Securities (except Registrable
Securities that the Holders have elected not to include in such Shelf
Registration Statement) or Securities that represent an unsold allotment for the
original offering thereof on an appropriate form under Rule 415 under the 1933
Act, or any similar rule that may be adopted by the SEC, and all amendments and
supplements to such registration statement, including post-effective amendments,
in each case, including the Prospectus contained therein, all exhibits thereto
and all material incorporated by reference therein.

         "TRANSFER AGENT" shall mean the transfer agent with respect to the
Preferred Stock and the Common Stock.

         "UNDERWRITERS" shall have the meaning set forth in Section 3 hereof.

         "UNDERWRITTEN REGISTRATION" or "UNDERWRITTEN OFFERING" shall mean a
registration in which Registrable Securities are sold to an Underwriter for
reoffering to the public.

         2. Registration under the 1933 Act.

                  (a) The Company shall prepare, and not later than 180 days
         following the date of original issuance of the Preferred Stock, shall
         use its reasonable best efforts to cause to be filed with the SEC, a
         Shelf Registration Statement providing for the sale by the Holders of
         all of the Registrable Securities. The Company shall use its reasonable
         best efforts to have the Shelf Registration Statement declared
         effective by the SEC on or prior to the date that is 210 days after the
         date of original issuance of the Preferred Stock. The Company agrees to
         use its reasonable best efforts to keep the Shelf Registration
         Statement continuously effective until the earlier of the expiration of
         the period referred to in Rule 144(k) under the 1933 Act with respect
         to the Registrable Securities or two years after the

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         issue date of the Preferred Stock or such shorter period that will
         terminate when all of the Registrable Securities covered by the Shelf
         Registration Statement have been sold pursuant to the Shelf
         Registration Statement. The Company further agrees to supplement or
         amend the Shelf Registration Statement if required by the rules,
         regulations or instructions applicable to the registration form used by
         the Company for such Shelf Registration Statement or by the 1933 Act or
         by any other rules and regulations thereunder for shelf registration or
         if reasonably requested by a Holder with respect to information
         relating to such Holder and required by applicable law to be included
         therein, and to use its reasonable best efforts to cause any such
         amendment to become effective and such Shelf Registration Statement to
         become usable as soon thereafter as practicable. The Company agrees to
         furnish to the Holders of Registrable Securities copies of any such
         supplement or amendment promptly after its being used or filed with the
         SEC.

                  (b) If the Registrable Securities include or consist of
         Preferred Stock, the Company shall set forth in any Shelf Registration
         Statement, as of the effective date of such Shelf Registration
         Statement, the Company's intention not to enter into any agreement or
         other contractual arrangement that would prohibit the Company from
         paying dividends in shares of Common Stock, as contemplated by the
         terms of the Preferred Stock.

                  (c) The Company shall pay all Registration Expenses in
         connection with the registration pursuant to Section 2(a). Each Holder
         shall pay all underwriting discounts, if any, and commissions and
         transfer taxes, if any, relating to the sale or disposition of such
         Holder's Registrable Securities pursuant to the Shelf Registration
         Statement.

                  (d) The Shelf Registration Statement filed pursuant to Section
         2(a) hereof will not be deemed to have become effective unless it has
         been declared effective by the SEC; provided, however, that, if, after
         it has been declared effective, the offering of Registrable Securities
         pursuant to the Shelf Registration Statement is interfered with by any
         stop order, injunction or other order or requirement of the SEC or any
         other governmental agency or court, the Shelf Registration Statement
         will be deemed not to be effective during the period of such
         interference until the offering of Registrable Securities pursuant to
         the Shelf Registration Statement may legally resume.

                  (e) Upon the occurrence of a Registration Default, Holders
         will be entitled to receive Additional Dividends as provided in the
         Certificate

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         of Designations or, if the Preferred Stock has been exchanged for
         Convertible Debentures, Additional Interest as provided in the
         Indenture.

                  (f) Without limiting the remedies available to the Initial
         Purchasers and the Holders, the Company acknowledges that any failure
         by the Company to comply with its obligations under Section 2(a) hereof
         may result in material irreparable injury to the Initial Purchasers or
         the Holders for which there is no adequate remedy at law, that it will
         not be possible to measure damages for such injuries precisely and
         that, in the event of any such failure, the Initial Purchasers or any
         Holder may obtain such relief as may be required to specifically
         enforce the Company's obligations under Section 2(a) hereof.

         3. Registration Procedures.

         In connection with the obligations of the Company with respect to the
Shelf Registration Statement pursuant to Section 2(a) hereof, the Company shall
reasonably promptly:

                  (a) prepare and file with the SEC a Shelf Registration
         Statement on the appropriate form under the 1933 Act, which form shall
         (x) be selected by the Company, (y) be available for the sale of the
         Registrable Securities by the selling Holders thereof and (z) comply as
         to form in all material respects with the requirements of the
         applicable form and include all financial statements required by the
         SEC to be filed therewith or incorporated by reference therein, and use
         its reasonable best efforts to cause the Shelf Registration Statement
         to become effective and remain effective in accordance with Section 2
         hereof;

                  (b) prepare and file with the SEC such amendments and post-
         effective amendments to the Shelf Registration Statement as may be
         necessary to keep the Shelf Registration Statement effective for the
         applicable period and cause each Prospectus to be supplemented by any
         required prospectus supplement and, as so supplemented, to be filed
         pursuant to Rule 424 under the 1933 Act; and keep each Prospectus
         current during the period described under Section 4(3) and Rule 174
         under the 1933 Act that is applicable to transactions by brokers or
         dealers with respect to the Registrable Securities;

                  (c) furnish to each Holder of Registrable Securities, to
         counsel for the Holders and for the Initial Purchasers (or, if
         applicable, separate counsel for the Holders) and to each Underwriter
         of an Underwritten Offering of Registrable Securities, if any, without
         charge, as many copies

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         of each Prospectus, including each preliminary Prospectus and any
         amendment or supplement thereto and such other documents as such Holder
         or Underwriter may reasonably request, in order to facilitate the
         public sale or other disposition of the Registrable Securities; and the
         Company consents to the use of such Prospectus and any amendment or
         supplement thereto in accordance with applicable law by each of the
         selling Holders of Registrable Securities and any such Underwriters in
         connection with the offering and sale of the Registrable Securities
         covered by and in the manner described in such Prospectus or any
         amendment or supplement thereto in accordance with applicable law;
         provided, however, that such consent is subject to compliance by the
         Holders and any such Underwriters with the second to last paragraph of
         Section 3;

                  (d) use its reasonable best efforts (i) to register or qualify
         the Registrable Securities under all applicable state securities or
         "blue sky" laws of such jurisdictions as any Holder of Registrable
         Securities covered by the Shelf Registration Statement shall reasonably
         request in writing by the time the Shelf Registration Statement is
         declared effective by the SEC and (ii) to cooperate with such Holders
         in connection with any filings required to be made with the National
         Association of Securities Dealers, Inc. and do any and all other
         customary acts and things which may be reasonably necessary or
         advisable to enable such Holder to consummate the disposition in each
         such jurisdiction of such Registrable Securities owned by such Holder;
         provided, however, that the Company shall not be required to (A)
         register or qualify as a foreign corporation or as a dealer in
         securities in any jurisdiction where it would not otherwise be required
         to register or qualify but for this Section 3(d), or (B) take any
         action that would subject it to any general service of process or to
         taxation in any such jurisdiction if it is not so subject;

                  (e) notify each Holder of Registrable Securities, counsel for
         the Holders and for the Initial Purchasers (or, if applicable, separate
         counsel for the Holders) promptly and, if requested by such Persons,
         confirm such advice in writing, (i) when the Shelf Registration
         Statement has become effective and when any post-effective amendment
         thereto has been filed and becomes effective, (ii) of any request by
         the SEC or any state securities authority for amendments and
         supplements to the Shelf Registration Statement and Prospectus or for
         additional information after the Shelf Registration Statement has
         become effective, (iii) of the issuance by the SEC or any state
         securities authority of any stop order suspending the effectiveness of
         the Shelf Registration Statement or the initiation of any proceedings
         for that purpose, (iv) if, between the effective date of the Shelf
         Registration Statement and the closing of any sale of Registrable

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         Securities covered thereby, the Company receives any notification with
         respect to the suspension of the qualification of the Registrable
         Securities for sale in any jurisdiction or the initiation of any
         proceeding for such purpose, (v) of the happening of any event during
         the period the Shelf Registration Statement is effective which makes
         any statement made in the Shelf Registration Statement or the related
         Prospectus untrue in any material respect or which requires the making
         of any changes in the Shelf Registration Statement or Prospectus in
         order to make the statements therein not misleading and (vi) of any
         determination by the Company that a post-effective amendment to the
         Shelf Registration Statement would be appropriate;

                  (f) make every reasonable effort to obtain the withdrawal of
         any order suspending the effectiveness of the Shelf Registration
         Statement at the earliest possible moment and provide prompt notice to
         each Holder of Registrable Securities of the withdrawal of any such
         order;

                  (g) furnish to each Holder of Registrable Securities, upon
         request and without charge, at least one conformed copy of the Shelf
         Registration Statement and any post-effective amendment thereto
         (without documents incorporated therein by reference or exhibits
         thereto, unless requested);

                  (h) in connection with any sale of Registrable Securities that
         will result in such securities no longer being Registrable Securities,
         cooperate with the selling Holders of Registrable Securities to
         facilitate the timely preparation and delivery of certificates
         representing Registrable Securities to be sold and not bearing any
         restrictive legends (unless required by applicable securities laws) and
         enable such Registrable Securities to be in such denominations and
         registered in such names as the selling Holders may reasonably request
         at least two business days prior to the closing of any sale of
         Registrable Securities;

                  (i) upon the occurrence of any event contemplated by Section
         3(e) hereof that so requires, use its reasonable best efforts to
         prepare and file with the SEC a supplement or post-effective amendment
         to the Shelf Registration Statement or the related Prospectus or any
         document incorporated therein by reference or file any other required
         document so that, as thereafter delivered to the purchasers of the
         Registrable Securities, such Prospectus will not contain any untrue
         statement of a material fact or omit to state a material fact necessary
         to make the statements therein, in the light of the circumstances under
         which they were made, not misleading. The Company agrees to notify the
         Holders of Registrable Securities to suspend use of the Prospectus as
         promptly as practicable after

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         the occurrence of such an event, and the Holders hereby agree to
         suspend use of the Prospectus until the Company has amended or
         supplemented the Prospectus to correct such misstatement or omission;

                  (j) a reasonable time prior to the filing of the Shelf
         Registration Statement, any Prospectus, any amendment to the Shelf
         Registration Statement or amendment or supplement to a Prospectus to be
         filed pursuant to the 1933 Act, provide copies of such document to
         Salomon Smith Barney and Morgan Stanley and their counsel and make such
         of the representatives of the Company as shall be reasonably requested
         by Salomon Smith Barney and Morgan Stanley or their counsel available
         for discussion of such document, and shall not at any time file or make
         any amendment to the Shelf Registration Statement, any Prospectus or
         any amendment of or supplement to the Shelf Registration Statement or a
         Prospectus, of which Salomon Smith Barney and Morgan Stanley and their
         counsel shall not have previously been advised and furnished a copy or
         to which Salomon Smith Barney and Morgan Stanley or their counsel shall
         reasonably object within two business days after receipt thereof;

                  (k) obtain a CUSIP number for all Registrable Securities not
         later than the effective date of the Shelf Registration Statement;

                  (l) if the Registrable Securities consist of or include
         Convertible Debentures, cause the Indenture to be qualified under the
         Trust Indenture Act of 1989, as amended (the "TIA"), in connection with
         the registration of the Registrable Securities, cooperate with the
         Trustee and the Holders to effect such changes to the Indenture as may
         be required for the Indenture to be so qualified in accordance with the
         terms of the TIA and execute, and use its best efforts to cause the
         Trustee to execute, all documents as may be required to effect such
         changes and all other forms and documents required to be filed with the
         SEC to enable the Indenture to be so qualified in a timely manner;

                  (m) make available for inspection by any Underwriter
         reasonably acceptable to the Company participating in any disposition
         pursuant to the Shelf Registration Statement, and counsel for the
         Holders reasonably acceptable to the Company, at reasonable times and
         in a reasonable manner, all financial and other records, material
         corporate documents and properties of the Company, and cause the
         respective officers, directors and employees of the Company to supply
         such information reasonably requested by any such representative,
         Underwriter, attorney or accountant in connection with the Shelf
         Registration Statement, in each case, that would customarily be
         reviewed or examined in connection with a "DUE

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         DILIGENCE" review in connection with filing a Shelf Registration
         Statement of the Company;

                  (n) if reasonably requested by any Holder of Registrable
         Securities covered by the Shelf Registration Statement, (i) as promptly
         as practicable incorporate in a Prospectus supplement or post-effective
         amendment such information with respect to such Holder as is required
         to be included therein in accordance with applicable law and (ii) make
         all required filings of such Prospectus supplement or such
         post-effective amendment as soon as the Company has received
         notification of the matters to be incorporated in such filing;
         provided, however, that the Company shall not be required to take any
         action pursuant to this Section 3(n) that would, in the opinion of
         counsel for the Company reasonably satisfactory to the Initial
         Purchasers, violate applicable law;

                  (o) cause all Registrable Securities covered by the Shelf
         Registration Statement (i) that consist of Common Stock to be listed on
         each securities exchange or quotation system on which similar
         securities issued by the Company are then listed, if so requested by
         the Majority Holders and (ii) that consist of Preferred Stock to be
         rated with Standard & Poors and Moody's Investors Service Inc., if so
         requested by the Majority Holders; and

                  (p) in the case of an Underwritten Offering pursuant to the
         Shelf Registration, upon the request of the Majority Holders of
         Registrable Securities included therein, enter into such customary
         agreements and take all such other customary actions in connection
         therewith (including those reasonably requested by counsel for the
         Holders) in order to expedite or facilitate the disposition of such
         Registrable Securities and in such connection, (i) to the extent
         possible, make such reasonable representations and warranties to the
         Holders and any Underwriters of such Registrable Securities with
         respect to the business of the Company and its subsidiaries, the Shelf
         Registration Statement, Prospectus and documents incorporated by
         reference or deemed incorporated by reference, if any, in each case, in
         form, substance and scope as were made by the Company in the Purchase
         Agreement and confirm the same if and when requested, (ii) obtain
         opinions of counsel to the Company (which counsel and opinions, in
         form, scope and substance, shall be reasonably satisfactory to the
         selling Holders and such Underwriters and their respective counsel)
         addressed to each selling Holder and Underwriter of Registrable
         Securities, covering the matters customarily covered in opinions
         requested in underwritten offerings, (iii) subject to the making of
         such representations as are customarily made to such accountants in

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         relation to their provision of such letters, obtain "cold comfort"
         letters from the independent certified public accountants of the
         Company (and, if necessary, any other certified public accountant of
         any subsidiary of the Company, or of any business acquired by the
         Company for which financial statements and financial data are or are
         required to be included in the Shelf Registration Statement) addressed
         to each selling Holder and Underwriter of Registrable Securities, such
         letters to be in customary form and covering matters of the type
         customarily covered in "cold comfort" letters in connection with
         underwritten offerings, and (iv) deliver such documents and
         certificates as may be reasonably requested by counsel for the Holders
         to evidence the continued validity of the representations and
         warranties of the Company made pursuant to clause (i) above and to
         evidence compliance with any customary conditions contained in an
         underwriting agreement.

         The Company may require each Holder of Registrable Securities to
promptly furnish to the Company such information regarding the Holders and the
proposed distribution by such Holder of such Registrable Securities as the
Company may from time to time reasonably request in writing. Notwithstanding
anything herein to the contrary, no Holder of Registrable Securities may include
any of its Registrable Securities in any Shelf Registration Statement pursuant
to this Agreement unless and until such Holder (i) furnishes to the Company in
writing within 20 days after receipt of a request therefor, the information
specified in Items 507 and 508 of Regulation S-K, as applicable, of the 1933 Act
for use in connection with any Shelf Registration Statement or Prospectus or
preliminary prospectus included therein, (ii) agrees to promptly furnish
additional information required to be disclosed in order to make the information
previously furnished to the Company by such Holder not materially misleading and
(iii) at the Company's request, acknowledges in writing its agreement to be
bound by the provisions of this Agreement in accordance with Section 5(d)
hereof. No Holder shall be entitled to Additional Dividends or Additional
Interest during any period in which exclusion of any Registrable Securities of
such Holder from any Shelf Registration Statement results from the operation of
this paragraph.

         Each Holder agrees that, upon receipt of any notice from the Company of
the happening of any event of the kind described in Section 3(e) hereof, such
Holder will forthwith discontinue disposition of Registrable Securities pursuant
to the Shelf Registration Statement until such Holder's receipt of the copies of
the supplemented or amended Prospectus contemplated by Section 3(i) hereof, and,
if so directed by the Company, such Holder will deliver to the Company (at its
expense) all copies in its possession, other than permanent file copies then in
such Holder's possession, of the Prospectus covering such Registrable Securities
current at the time of receipt of such notice. If the Company shall give any
such

                                       12
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notice to suspend the disposition of Registrable Securities pursuant to the
Shelf Registration Statement, the Company shall extend the period during which
the Shelf Registration Statement shall be maintained effective pursuant to this
Agreement by the number of days during the period from and including the date of
the giving of such notice to and including the date when the Holders shall have
received copies of the supplemented or amended Prospectus necessary to resume
such dispositions. Such suspensions may not exceed 90 days in the aggregate in
any consecutive 365-day period.

         The Holders of Registrable Securities covered by the Shelf Registration
Statement who desire to do so may sell such Registrable Securities in an
Underwritten Offering. In any such Underwritten Offering, the investment banker
or investment bankers and manager or managers (the "UNDERWRITERS") that will
administer the offering will be selected by the Majority Holders of the
Registrable Securities included in such offering and shall be reasonably
acceptable to the Company.

         4. Indemnification and Contribution.

                  (a) The Company agrees to indemnify and hold harmless the
         Initial Purchasers, each other Holder and each Person, if any, who
         controls the Initial Purchasers or any other Holder within the meaning
         of either Section 15 of the 1933 Act or Section 20 of the 1934 Act, or
         is under common control with, or is controlled by any Initial Purchaser
         or any other Holder, from and against any and all losses, claims,
         damages and liabilities (including, without limitation, any legal or
         other expenses incurred in connection with defending or investigating
         any such action or claim) caused by any untrue statement or alleged
         untrue statement of a material fact contained in the Shelf Registration
         Statement (or any amendment thereto pursuant to which Registrable
         Securities were registered under the 1933 Act, including all documents
         incorporated therein by reference), or caused by any omission or
         alleged omission to state therein a material fact necessary to make the
         statements therein in light of the circumstances under which they were
         made not misleading, or caused by any untrue statement or alleged
         untrue statement of a material fact contained in any Prospectus (as
         amended or supplemented if the Company shall have furnished any
         amendments or supplements thereto, including all documents incorporated
         therein by reference), or caused by any omission or alleged omission to
         state therein a material fact necessary to make the statements therein,
         in the light of the circumstances under which they were made, not
         misleading, except insofar as such losses, claims, damages or
         liabilities are caused by any such untrue statement or omission or
         alleged untrue statement or omission based upon information relating to
         any Initial

                                       13
<PAGE>
         Purchaser or other Holder furnished to the Company in writing by such
         Initial Purchaser or other Holder through you expressly for use
         therein; provided, however, that the foregoing indemnity with respect
         to the Preliminary Memorandum shall not inure to the benefit of the
         Initial Purchaser, other Holder or controlling person from whom the
         person asserting any such losses, claims, damages, liabilities or
         actions in respect thereof purchased Securities to the extent that any
         such losses, claims, damages, liabilities or actions in respect thereof
         result from such Initial Purchaser's, other Holder's or controlling
         person's selling Securities to a person in an initial resale to whom
         there was not sent or given, at or prior to the written confirmation of
         the sale of such Securities, a copy of the Final Memorandum (as amended
         or supplemented), if the Company had previously furnished a copy of
         such amendments or supplements to such Initial Purchaser, other Holder
         or controlling person prior to confirmation of the sale of such
         Securities to such person by such Initial Purchaser, other Holder or
         controlling person, and the losses, claims, damages, liabilities or
         actions in respect thereof of such Initial Purchaser, other Holder or
         controlling person result from an untrue statement or omission of a
         material fact contained in the Preliminary Memorandum, which was
         corrected in the Final Memorandum (as amended or supplemented).

                  (b) Each Holder agrees, severally and not jointly, to
         indemnify and hold harmless the Company, the Initial Purchasers, each
         affiliate of an Initial Purchaser which participated in the
         distribution of the Securities and each other selling Holder, and each
         of their respective directors, officers who sign the Shelf Registration
         Statement, and any Person who controls the Company, any Initial
         Purchaser and each other selling Holder within the meaning of Section
         15 of the Act or Section 20 of the 1934 Act, to the same extent as the
         foregoing indemnity from the Company to the Initial Purchasers and
         other Holders, but only with reference to such untrue statements or
         omissions, or such alleged untrue statements or omissions, contained in
         the Shelf Registration Statement (or any such amendment thereto) based
         upon information relating to any Initial Purchaser or other Holder
         furnished in writing by or on behalf of such Initial Purchaser or other
         Holder expressly for use in the Shelf Registration Statement (or any
         amendment thereto) or any Prospectus (or any amendment or supplement
         thereto).

                  (c) In case any proceeding (including any governmental
         investigation) shall be instituted involving any person in respect of
         which indemnity may be sought pursuant to Section 4(a) or 4(b), such
         Person (the "INDEMNIFIED PERSON") shall promptly notify the Person
         against whom such indemnity may be sought (the "INDEMNIFYING PERSON")
         in writing and the Indemnifying Person, upon request of the Indemnified

                                       14
<PAGE>
         Person, shall retain one counsel reasonably satisfactory to the
         Indemnified Person to represent the Indemnified Person and any others
         the Indemnifying Person may designate in such proceeding and shall pay
         the fees and disbursements of such counsel related to such proceeding.
         In any such proceeding, any Indemnified Person shall have the right to
         retain its own counsel, but the fees and expenses of such counsel shall
         be at the expense of such Indemnified Person unless (i) the
         Indemnifying Person and the Indemnified Person shall have mutually
         agreed to the retention of such counsel or (ii) the named parties to
         any such proceeding (including any impleaded parties) include both the
         Indemnifying Person and the Indemnified Person and representation of
         both parties by the same counsel would be inappropriate under
         applicable standards of professional conduct due to actual or potential
         differing interests between them. It is understood that the
         Indemnifying Person shall not, in respect of the legal expenses of any
         Indemnified Person in connection with any proceeding or related
         proceedings in the same jurisdiction, be liable for the fees and
         expenses of more than one separate firm (in addition to any local
         counsel) for all such Indemnified Persons and that all such fees and
         expenses shall be reimbursed as they are incurred. Such firm shall be
         designated in writing by Salomon Smith Barney and Morgan Stanley, in
         the case of persons indemnified pursuant to Section 4(a), and by the
         Company, in the case of persons indemnified pursuant to Section 4(b).
         The Indemnifying Person shall not be liable for any settlement of any
         proceeding effected without its written consent, but if settled with
         such consent or if there be a final judgment for the plaintiff, the
         Indemnifying Person agrees to indemnify the Indemnified Person from and
         against any loss or liability by reason of such settlement or judgment.
         No Indemnifying Person shall, without the prior written consent of the
         Indemnified Person, effect any settlement of any pending or threatened
         proceeding in respect of which any Indemnified Person is or could have
         been a party and indemnity could have been sought hereunder by such
         Indemnified Person, unless such settlement includes an unconditional
         release of such Indemnified Person from all liability on claims that
         are the subject matter of such proceeding.

                  (d) To the extent the indemnification provided for in Section
         4(a) or 4(b) is unavailable to an Indemnified Person or insufficient in
         respect of any losses, claims, damages or liabilities referred to
         therein, then each Indemnifying Person under such paragraph, in lieu of
         indemnifying such Indemnified Person thereunder, shall contribute to
         the amount paid or payable by such Indemnified Person as a result of
         such losses, claims, damages or liabilities (i) in such proportion as
         is appropriate to reflect the relative benefits received by the Company
         on the one hand and the Holders on the other hand from the offering of
         the Securities or (ii) if the allocation provided by clause 4(d)(i)
         above is not permitted by applicable

                                       15
<PAGE>
         law, in such proportion as is appropriate to reflect not only the
         relative benefits referred to in clause 4(d)(i) above but also the
         relative fault of the Company on the one hand and of the Holders on the
         other hand in connection with the statements or omissions that resulted
         in such losses, claims, damages or liabilities, as well as any other
         relevant equitable considerations.

                  (e) The Company and each Holder agree that it would not be
         just or equitable if contribution pursuant to this Section 4 were
         determined by pro rata allocation or by any other method of allocation
         that does not take account of the equitable considerations referred to
         in Section 4(d) above. The amount paid or payable by an Indemnified
         Person as a result of the losses, claims, damages and liabilities
         referred to in Section 4(d) shall be deemed to include, subject to the
         limitations set forth above, any legal or other expenses reasonably
         incurred by such Indemnified Person in connection with investigating or
         defending any such action or claim. Notwithstanding the provisions of
         this Section 4, no Holder shall be required to contribute any amount in
         excess of the amount by which the total price at which Registrable
         Securities were sold by such Holder exceeds the amount of any damages
         that such Holder has otherwise been required to pay by reason of such
         untrue or alleged untrue statement or omission or alleged omission. No
         Person guilty of fraudulent misrepresentation (within the meaning of
         Section 11(f) of the 1933 Act) shall be entitled to contribution from
         any Person who was not guilty of such fraudulent misrepresentation. The
         Holders' respective obligations to contribute pursuant to this Section
         are several in proportion to the aggregate principal amount of
         Registrable Securities sold by them pursuant to the Shelf Registration
         Statement. The remedies provided for in this Section 4 are not
         exclusive and shall not limit any rights or remedies which may
         otherwise be available to any Indemnified Party at law or in equity.

                  (f) Any losses, claims, damages or liabilities for which an
         Indemnified Person is entitled to indemnification or contribution under
         this Section shall be paid by the Indemnifying Person to the
         Indemnified Person as such losses, claims, damages or liabilities are
         incurred. The indemnity and contribution agreements contained in this
         Section 4 and the representations and warranties of the Company
         contained in this Agreement shall remain operative and in full force
         and effect, regardless of (i) any investigation made by or on behalf of
         any Initial Purchaser, any Holder or any Person controlling any Initial
         Purchaser, any Holder, the Company's directors or officers or any
         Person controlling the Company, (ii) any termination of this Agreement
         and (iii) any sale of Registrable Securities pursuant to the Shelf
         Registration Statement.

                                       16
<PAGE>
           5.   Miscellaneous.

                  (a) No Inconsistent Agreements. The Company has not entered
         into, and on or after the date of this Agreement will not enter into,
         any agreement which is inconsistent with the rights granted to the
         Holders of Registrable Securities in this Agreement or otherwise
         conflicts with the provisions hereof. The rights granted to the Holders
         hereunder do not in any way conflict with and are not inconsistent with
         the rights granted to the holders of the Company's other issued and
         outstanding securities under any such agreements.

                  (b) Amendments and Waivers. The provisions of this Agreement,
         including the provisions of this sentence, may not be amended, modified
         or supplemented, and waivers or consents to departures from the
         provisions hereof may not be given unless the Company has obtained the
         written consent of Holders of at least a majority in aggregate
         principal amount of the outstanding Registrable Securities affected by
         such amendment, modification, supplement, waiver or consent; provided,
         however, that no amendment, modification, supplement, waiver or consent
         to any departure from the provisions of Section 4 hereof shall be
         effective as against any Holder of Registrable Securities unless
         consented to in writing by such Holder.

                  (c) Notices. All notices and other communications provided for
         or permitted hereunder shall be made in writing by hand-delivery,
         registered or certified first-class mail, telex, telecopier, or any
         courier guaranteeing overnight delivery (i) if to a Holder, at the most
         current address set forth in the records of the Transfer Agent, which
         address initially is, with respect to the Initial Purchasers, the
         address set forth in the Purchase Agreement; and (ii) if to the
         Company, initially at the Company's address set forth in the Purchase
         Agreement and thereafter at such other address, notice of which is
         given in accordance with the provisions of this Section. All such
         notices and communications shall be deemed to have been duly given at
         the time delivered, if personally delivered; five business days after
         being deposited in the mail, postage pre-paid, if mailed; when receipt
         is acknowledged, if telecopied; and on the next business day if timely
         delivered to an air courier guaranteeing overnight delivery.

                  (d) Successors and Assigns. This Agreement shall inure to the
         benefit of and be binding upon the successors, assigns and transferees
         of each of the parties, including, without limitation and without the
         need for

                                       17
<PAGE>
         an express assignment or assumption, subsequent Holders; provided that
         nothing herein shall be deemed to permit any assignment, transfer or
         other disposition of Registrable Securities in violation of the terms
         of the Purchase Agreement or the Certificate of Designations. If any
         transferee of any Holder shall acquire Registrable Securities, in any
         manner, whether by operation of law or otherwise, such Registrable
         Securities shall be held subject to all of the terms of this Agreement
         and by taking and holding such Registrable Securities, such Person
         shall be conclusively deemed to have agreed to be bound by and to
         perform all of the terms and provisions of this Agreement and such
         Person shall be entitled to the benefits hereof. The Initial Purchasers
         shall have no liability or obligation to the Company with respect to
         any failure by any other Holder to comply with, or any breach by any
         other Holder of, the obligations of such Holder under this Agreement.

                  (e) Purchases and Sales of Securities. The Company shall not,
         and shall cause its affiliates (as defined in rule 405 under the 1993
         Act) not to, purchase and then resell or otherwise transfer any
         Securities other than to the Company or its affiliates.

                  (f) Third Party Beneficiary. Each Holder shall be a third
         party beneficiary to the agreements made hereunder between the Company,
         on the one hand, and the Initial Purchasers, on the other hand, and
         shall have the right to enforce such agreements directly to the extent
         it deems such enforcement necessary or advisable to protect its rights
         or the rights of Holders hereunder.

                  (g) Counterparts. This Agreement may be signed in any number
         of counterparts, each of which shall be an original, with the same
         effect as if the signatures thereto and hereto were upon the same
         instrument.

                  (h) Headings. The headings of the sections of this Agreement
         have been inserted for convenience of reference only and shall not be
         deemed a part of this Agreement.

                  (i) Governing Law. This Agreement shall be governed by and
         construed in accordance with the internal laws of the State of New
         York.

                  (j) Severability. In the event that one or more of the
         provisions contained herein, or the application thereof in any
         circumstances, is held invalid, illegal or unenforceable, the validity,
         legality and enforceability of any such provision in every other
         respect and of the remaining provisions contained herein shall not be
         affected or impaired thereby.

                                       18
<PAGE>
         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first written above.

                                            LUCENT TECHNOLOGIES INC.


                                            By  /s/ Kevin G. DaSilva
                                               --------------------------------
                                               Name: Kevin G. DaSilva
                                               Title: Assistant Treasurer


SALOMON SMITH BARNEY INC.
MORGAN STANLEY & CO. INCORPORATED

For themselves and as Representatives of
the other Initial Purchasers


By: SALOMON SMITH BARNEY INC.


By /s/ Brooke Schooley
   -------------------------------------
   Name: Brooke Schooley
   Title: Vice President


By: MORGAN STANLEY & CO. INCORPORATED


By  /s/ Kenneth G. Pott
   -------------------------------------
   Name: Kenneth G. Pott
   Title: Executive Director