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                                                                     Exhibit 4.3

                          REGISTRATION RIGHTS AGREEMENT

                          Dated as of December 21, 2005

                                     between

                         CENTENNIAL COMMUNICATIONS CORP.

                                       and

                         CREDIT SUISSE FIRST BOSTON LLC

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                          REGISTRATION RIGHTS AGREEMENT

          THIS REGISTRATION RIGHTS AGREEMENT (the "Agreement") is made and
entered into as of December 21, 2005, between CENTENNIAL COMMUNICATIONS CORP., a
Delaware corporation (the "Issuer"), and CREDIT SUISSE FIRST BOSTON LLC (the
"Initial Purchaser").

          This Agreement is made pursuant to the Purchase Agreement dated
December 13, 2005, between the Issuer and the Initial Purchaser (the "Purchase
Agreement"), which provides for the sale by the Issuer to the Initial Purchaser
of an aggregate of $350,000,000 principal amount of the Issuer's Senior Floating
Rate Notes due 2013 (the "Securities"). In order to induce the Initial Purchaser
to enter into the Purchase Agreement, the Issuer has agreed to provide to the
Initial Purchaser and its direct and indirect transferees the registration
rights 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:

          1.   Definitions.

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

          "10% Senior Notes due 2013" shall mean the 10% Senior Notes due 2013
     of the Issuer issued pursuant to that certain indenture, dated as of
     December 21, 2005, between the Issuer and U.S. Bank National Association,
     as trustee.

          "10% Senior Notes Indenture" shall mean the indenture relating to the
     10% Senior Notes due 2013 dated as of December 21, 2005, between the Issuer
     and U.S. Bank National Association, as trustee.

          "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.

          "Additional Interest" shall have the meaning set forth in Section
     2(d).

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

          "Consummate" An Exchange Offer shall be deemed "Consummated" for
purposes of this Agreement upon the occurrence of (a) the filing and
effectiveness under the 1933 Act of the Exchange Offer Registration Statement
relating to the Exchange Securities to be issued in the Exchange Offer, (b) the
maintenance of such Exchange Offer Registration Statement continuously effective
and the keeping of the Exchange Offer open for a period not less than the period
required pursuant to Section 2(a) hereof and (c) the delivery by the Company to
the Registrar under the Indenture of Exchange Securities in the same aggregate
principal amount as the aggregate principal amount of Securities tendered by
Holders thereof pursuant to the Exchange Offer.

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          "Exchange Dates" shall have the meaning set forth in Section 2(a)(ii).

          "Exchange Offer" shall mean the exchange offer by the Issuer of
     Exchange Securities for Registrable Securities pursuant to Section 2(a)
     hereof.

          "Exchange Offer Registration" shall mean a registration under the 1933
     Act effected pursuant to Section 2(a) hereof.

          "Exchange Offer Registration Statement" shall mean an exchange offer
     registration statement on Form S-4 (or, if applicable, on another
     appropriate form) and all amendments and supplements to such registration
     statement, in each case including the Prospectus contained therein, all
     exhibits thereto and all material incorporated by reference therein.

          "Exchange Securities" shall mean securities issued by the Issuer under
     the Indenture containing terms identical to the Securities (except that the
     Exchange Securities will not contain restrictions on transfer or Additional
     Interest) and to be offered to Holders of Securities in exchange for
     Securities pursuant to the Exchange Offer.

          "Filing Date" means (i) with respect to an Exchange Offer Registration
     Statement or the Shelf Registration Statement required to be filed pursuant
     to Section 2(b)(i) or (ii), the earlier of the date of the filing thereof
     with the SEC and the 120th day after the Closing Date and (ii) with respect
     to the Shelf Registration Statement required to be filed pursuant to
     Section 2(b)(iii), the 60th day after the delivery of a notice pursuant to
     Section 2(b)(iii).

          "Holder" shall mean the Initial Purchaser, for so long as it owns any
     Registrable Securities, and each of its successors, assigns and direct and
     indirect transferees who become registered owners of Registrable Securities
     under the Indenture; provided that for purposes of Sections 4 and 5 of this
     Agreement, the term "Holder" shall include Participating Broker-Dealers (as
     defined in Section 4(a)).

          "Indenture" shall mean the Indenture relating to the Securities dated
     as of December 21, 2005 between the Issuer and U.S. Bank National
     Association, as trustee, and as the same may be amended from time to time
     in accordance with the terms thereof.

          "Issuer" shall have the meaning set forth in the preamble and shall
     also include successors of the Issuer.

          "Majority Holders" shall mean the Holders of a majority of the
     aggregate principal amount of outstanding Registrable Securities; provided
     that whenever the consent or approval of Holders of a specified percentage
     of Registrable Securities is required hereunder, Registrable Securities
     held by the Issuer or any of its affiliates (as such term is defined in
     Rule 405 under the 1933 Act) (other than the Initial Purchaser or
     subsequent Holders of Registrable Securities if such subsequent holders are
     deemed to be such affiliates solely by reason of their holding of 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.


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          "Participating Broker-Dealer" shall have the meaning set forth in
     Section 4(a).

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

          "Initial Purchaser" 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 Registration
     Statement, including any preliminary prospectus, 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 (i) when a
     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 Registration Statement, (ii) when such
     Securities have been sold to the public pursuant to Rule 144 and any
     restrictive legends have been removed (or any similar provision then in
     force, but not Rule 144A) under the 1933 Act, (iii) when such Securities
     shall have ceased to be outstanding or (iv) when such Securities are
     eligible to be sold pursuant to Rule 144(k).

          "Registration Expenses" shall mean any and all expenses incident to
     performance of or compliance by the Issuer 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 for
     any underwriters or Holders in connection with blue sky qualification of
     any of the Exchange Securities or Registrable Securities), (iii) all
     expenses of any Persons in preparing or assisting in preparing, word
     processing, printing and distributing any Registration Statement, any
     Prospectus, any amendments or supplements thereto, any underwriting
     agreements, securities sales agreements and other documents relating to the
     performance of and compliance with this Agreement, (iv) all rating agency
     fees, (v) all fees and disbursements relating to the qualification of the
     Indenture under applicable securities laws, (vi) the fees and disbursements
     of the Trustee and its counsel, (vii) the fees and disbursements of counsel
     for the Issuer and, in the case of a Shelf Registration Statement, the fees
     and disbursements of one counsel for the Holders (which counsel shall be
     selected by the Majority Holders and which counsel may also be counsel for
     the Initial Purchaser) and (viii) the fees and disbursements of the
     independent public accountants of the Issuer, including the expenses of any
     special audits or "cold comfort" letters required by or incident to such
     performance and compliance, but excluding fees and expenses of counsel to
     the underwriters (other than fees and expenses set forth in clause (ii)
     above) or the Holders and underwriting discounts and commissions and


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     transfer taxes, if any, relating to the sale or disposition of Registrable
     Securities by a Holder.

          "Registration Statement" shall mean any registration statement of the
     Issuer that covers any of the Exchange Securities or Registrable Securities
     pursuant to the provisions of this Agreement and all amendments and
     supplements to any 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.

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

          "SEC" shall mean the Securities and Exchange Commission.

          "Shelf Registration" shall mean a registration effected pursuant to
     Section 2(b) hereof.

          "Shelf Registration Statement" shall mean a "shelf" registration
     statement of the Issuer pursuant to the provisions of Section 2(b) of this
     Agreement which covers all of the Registrable Securities and, at the
     Company's option, the Company's 10% Senior Notes due 2013 (but no other
     securities unless approved by the Holders whose Registrable Securities are
     covered by such Shelf Registration Statement) 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; provided, however that such Shelf Registration Statement
     shall cover any additional securities issued under the Indenture.

          "Trustee" shall mean the trustee with respect to the Securities under
     the Indenture.

          "Underwriter" 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) To the extent not prohibited by any applicable law or applicable
interpretation of the Staff of the SEC, the Issuer shall use its reasonable best
efforts to cause to be filed an Exchange Offer Registration Statement covering
the offer by the Issuer to the Holders to exchange all of the Registrable
Securities for Exchange Securities and to have such Registration Statement
remain effective until the closing of the Exchange Offer. The Issuer shall
commence the Exchange Offer promptly after the Exchange Offer Registration
Statement has been declared effective by the SEC and use its reasonable best
efforts to have the Exchange Offer Consummated not later than 210 days following
the Closing Date.

          The Issuer shall commence the Exchange Offer by mailing the related
exchange offer Prospectus and any accompanying documents to each Holder (it
being agreed that delivery


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to DTC shall constitute mailing) stating, in addition to such other disclosures
as are required by applicable law:

          (i) that the Exchange Offer is being made pursuant to this
     Registration Rights Agreement and that all Registrable Securities validly
     tendered will be accepted for exchange;

          (ii) the dates of acceptance for exchange (which shall be a period of
     at least 20 business days from the date such notice is mailed) (the
     "Exchange Dates");

          (iii) that any Registrable Security not tendered will remain
     outstanding and continue to accrue interest, but will not retain any rights
     under this Registration Rights Agreement;

          (iv) unless the Registrable Security is held through DTC, that Holders
     electing to have a Registrable Security exchanged pursuant to the Exchange
     Offer will be required to surrender such Registrable Security, together
     with the enclosed letters of transmittal, to the institution and at the
     address specified in the notice prior to the close of business on the last
     Exchange Date; and

          (v) that Holders will be entitled to withdraw their election, not
     later than the close of business on the last Exchange Date, by sending to
     the institution and at the address specified in the notice a telegram,
     telex, facsimile transmission or letter setting forth the name of such
     Holder, the principal amount of Registrable Securities delivered for
     exchange and a statement that such Holder is withdrawing his election to
     have such Securities exchanged.

          As soon as practicable after the last Exchange Date, the Issuer shall:

          (i) accept for exchange Registrable Securities or portions thereof
     validly tendered and not validly withdrawn pursuant to the Exchange Offer;
     and

          (ii) deliver, or cause to be delivered, to the Trustee for
     cancellation all Registrable Securities or portions thereof so accepted for
     exchange by the Issuer and issue, and cause the Trustee to promptly
     authenticate and mail to each Holder, an Exchange Security equal in
     principal amount to the principal amount of the Registrable Securities
     surrendered by such Holder.

The Issuer shall use its reasonable best efforts to complete the Exchange Offer
as provided above and shall comply with the applicable requirements of the 1933
Act, the 1934 Act and other applicable laws and regulations in connection with
the Exchange Offer. The Exchange Offer shall not be subject to any conditions,
other than that the Exchange Offer does not violate applicable law or any
applicable interpretation of the Staff of the SEC. No securities other than the
Securities or any additional securities issued under the Indenture and, at the
Company's option, the Company's 10% Senior Notes due 2013 or any additional
securities issued under the 10% Senior Notes Indenture, shall be included in the
Exchange Offer Registration Statement. The Issuer shall inform the Initial
Purchaser of the names and addresses of the Holders to whom the Exchange Offer
is made, and the Initial Purchaser shall have the right, subject to applicable


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law, to contact such Holders and otherwise facilitate the tender of Registrable
Securities in the Exchange Offer.

          (b) In the event that (i) the Issuer determines that the Exchange
Offer Registration provided for in Section 2(a) above is not available or may
not be Consummated as soon as practicable after the last Exchange Date because
it would violate applicable law or the applicable interpretations of the Staff
of the SEC, (ii) the Exchange Offer is not for any other reason Consummated
within 210 days after the Closing Date or (iii) if (A) the Initial Purchaser
holds any Securities acquired by it that have, or that are reasonably likely to
be determined to have, the status of an unsold allotment in an initial
distribution, or (B) any Holder is not entitled to participate in the Exchange
Offer, and any such Holder or Placement Agent so requests in writing on or prior
to the 60th day after the consummation of the Exchange Offer, the Issuer shall
use its reasonable best efforts to cause to be filed as soon as reasonably
practicable after receipt of such notice, a Shelf Registration Statement
providing for the sale by the Holders of all of such Registrable Securities
referred to in clause (iii) and shall use its reasonable best efforts to have
such Shelf Registration Statement declared effective by the SEC. In the event
the Issuer is required to file a Shelf Registration Statement solely as a result
of the matters referred to in clause (iii) of the preceding sentence, the Issuer
shall file and use its reasonable best efforts to have declared effective by the
SEC both an Exchange Offer Registration Statement pursuant to Section 2(a) with
respect to such Registrable Securities referred to in clause (iii) and a Shelf
Registration Statement (which may be a combined Registration Statement with the
Exchange Offer Registration Statement) with respect to offers and sales of
Registrable Securities held by the Initial Purchaser or such other Holders after
completion of the Exchange Offer. The Issuer agrees to use its reasonable best
efforts to keep the Shelf Registration Statement continuously effective until
the expiration of the period referred to in Rule 144(k) with respect to the
Registrable Securities 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 Issuer 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
Issuer 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
to use its reasonable best efforts to cause any such amendment to become
effective and such Shelf Registration Statement to become usable as soon as
thereafter practicable. The Issuer 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.

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

          (d) An Exchange Offer Registration Statement pursuant to Section 2(a)
hereof or a Shelf Registration Statement pursuant to Section 2(b) 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 a Shelf


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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, such
Registration Statement will be deemed not to have become effective during the
period of such interference until the offering of Registrable Securities
pursuant to such Registration Statement may legally resume. In the event the
Exchange Offer is not Consummated and the Shelf Registration Statement is not
declared effective as set forth below, then, the interest rate on the
Registrable Securities will be increased (the "Additional Interest") as follows:

          (i) if (A) neither the Exchange Offer Registration Statement nor a
     Shelf Registration Statement has been filed with the SEC on or prior to the
     120th day after the Closing Date or (B) the Issuer is required to file a
     Shelf Registration Statement pursuant to Section 2(b)(iii) hereof and such
     Shelf Registration Statement is not filed on or prior to the Filing Date
     applicable thereto then, commencing on the day after either such 120th day
     in the case of clause (A) or the day after such Filing Date in the case of
     clause (B), Additional Interest shall accrue on the principal amount of the
     Registrable Securities at a rate of 0.50% per annum; or

          (ii) if (A) neither the Exchange Offer Registration Statement nor a
     Shelf Registration Statement is declared effective by the SEC on or prior
     to the 180th day after the Closing Date or (B) the Issuer is required to
     file a Shelf Registration Statement pursuant to Section 2(b)(iii) hereof
     and such Shelf Registration Statement is not declared effective by the SEC
     on or prior to the 60th day following the Filing Date applicable thereto
     then, commencing on the day after either such 180th day in the case of
     clause (A) or the day after the Filing Date in the case of clause (B),
     Additional Interest shall accrue on the principal amount of the Registrable
     Securities at a rate of 0.50% per annum; or

          (iii) subject to Sections 2(f) and 2(g) if (A) the Issuer has not
     exchanged Exchange Securities for all Securities validly tendered in
     accordance with the terms of the Exchange Offer on or prior to the 210th
     day after the Closing Date or (B) if applicable, the Shelf Registration
     Statement has been declared effective and such Shelf Registration Statement
     ceases to be effective at any time prior to the second anniversary of the
     Closing Date (or, if earlier, the date when all Securities have been
     disposed of thereunder), then Additional Interest shall accrue on the
     principal amount of the Registrable Securities at a rate of 0.50% per annum
     commencing on (x) the day after the 210th day after the Closing Date, in
     the case of (A) above, or (y) the day after the day such Shelf Registration
     Statement ceases to be effective in the case of (B) above;

provided, further, that the Issuer shall in no event be required to pay
additional interest for more than one event in clauses (i), (ii), or (iii) at
any one time; provided further, however, that (1) upon the filing of the
Exchange Offer Registration Statement or a Shelf Registration Statement (in the
case of clause (i)(A) above) or a Shelf Registration Statement (in the case of
clause (ii)(B) above, (2) upon the effectiveness of the Exchange Offer
Registration or a Shelf Registration Statement (in the case of clause (ii)(A)
above) or a Shelf Registration (in the case of (i)(B) above), or (3) upon the
exchange of Exchange Securities for all Registrable Securities tendered (in the
case of clause (iii)(A) above), or (4) upon the effectiveness of the Shelf
Registration Statement which had ceased to remain effective (in the case of
clause (iii)(B) above), Additional


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Interest on the Securities as a result of such clause (or the relevant subclause
thereof), as the case may be, shall cease to accrue.

          (e) Without limiting the remedies available to the Initial Purchaser
and the Holders, the Issuer acknowledges that any failure by it to comply with
its obligations under Section 2(a) and Section 2(b) hereof may result in
material irreparable injury to the Initial Purchaser 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 Purchaser or any Holder may obtain such relief as may be required to
specifically enforce the Issuer's obligations under Section 2(a) and Section
2(b) hereof.

          (f) No Holder of Registrable Securities may include any of its
Registrable Securities in any Shelf Registration unless and until such Holder
furnishes to the Issuer, in writing within 20 days after receipt of a request
therefor, the information with respect to such Holder specified in Items 507 and
508 (as applicable) of Regulation S-K under the 1933 Act and any other
applicable rules, regulations or policies of the SEC for use in connection with
any Shelf Registration or Prospectus included therein, on a form to be provided
by the Issuer. No Holder of Registrable Securities shall be entitled to
Additional Interest pursuant to Section 2(d) hereof unless and until such Holder
shall have provided all such information. Each selling Holder agrees to furnish
promptly to the Issuer additional information to be disclosed so that the
information previously furnished to the Issuer by such Holder does not contain
any untrue statement of a material fact or omit to state a material fact
required to be stated therein or necessary to make the statements therein not
misleading.

          (g) Additional Interest shall not accrue with respect to an event
listed in Sections 2(d) hereof (each, a "Registration Default") if (i) such
Registration Default under Section 2(d)(iii)(B) hereof occurs because of the
filing of a post-effective amendment to such Registration Statement to
incorporate annual audited financial information with respect to the Issuer
where such post-effective amendment is not yet effective and needs to be
declared effective to permit Holders to use the related Prospectus, (ii) such
Registration Default occurs because of the occurrence of other material events
or developments with respect to the Issuer that would need to be described in
such Registration Statement or the related Prospectus, and the effectiveness of
such Registration Statement is reasonably required to be suspended while such
Registration Statement and related Prospectus are amended or supplemented to
reflect such events or developments, (iii) such Registration Default results
from the suspension of the effectiveness of such Registration Statement because
of the existence of material events or developments with respect to the Issuer
or any of its affiliates, the disclosure of which the Issuer determines in good
faith would have a material adverse effect on its business, operations or
prospects, or (iv) such Registration Default results from the suspension of the
effectiveness of such Registration Statement because the Issuer does not wish to
disclose publicly a pending material business transaction that has not yet been
publicly disclosed; provided, however, that if any such Registration Default
exists and continues on more than 45 consecutive days and an aggregate of 90
days in any 12-month period, Additional Interest shall accrue and be payable in
accordance with Section 2(d) hereof from the 46th or 91st day, as the case may
be, on which any such Registration Default exists, and shall continue to accrue
until the date on which such Registration Default is cured.


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          3.   Registration Procedures.

          In connection with the obligations of the Issuer with respect to the
Registration Statements pursuant to Section 2(a) and Section 2(b) hereof, the
Issuer shall as soon as reasonably possible:

          (a) prepare and file with the SEC a Registration Statement on the
     appropriate form under the 1933 Act, which form (x) shall be selected by
     the Issuer, (y) shall, in the case of a Shelf Registration, be available
     for the sale of the Registrable Securities by the selling Holders thereof
     and (z) shall 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, and use its reasonable best
     efforts to cause such 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 each Registration Statement as may be necessary to keep such
     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; to
     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 or Exchange
     Securities;

          (c) in the case of a Shelf Registration, furnish to each Holder of
     Registrable Securities, to counsel for the Initial Purchaser, to counsel
     for the Holders and to each Underwriter of an Underwritten Offering of
     Registrable Securities, if any, without charge, as many copies 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 Issuer 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;

          (d) use its reasonable best efforts 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 a Registration Statement shall reasonably request in writing by the time
     the applicable Registration Statement is declared effective by the SEC, 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 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 Issuer shall not be required to (i) qualify as a foreign
     corporation or as a dealer in securities in any jurisdiction where it would
     not otherwise be required to qualify but for this Section 3(d),


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     (ii) file any general consent to service of process or (iii) subject itself
     to taxation in any such jurisdiction if it is not so subject;

          (e) in the case of a Shelf Registration, notify each Holder of
     Registrable Securities, counsel for the Holders and counsel for the Initial
     Purchaser promptly and, if requested by any such Holder or counsel, confirm
     such advice in writing (i) when a 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 a Registration Statement and
     Prospectus or for additional information after the 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 a
     Registration Statement or the initiation of any proceedings for that
     purpose, (iv) if, between the effective date of a Registration Statement
     and the closing of any sale of Registrable Securities covered thereby, the
     representations and warranties of the Issuer contained in any underwriting
     agreement, securities sales agreement or other similar agreement, if any,
     relating to the offering cease to be true and correct in all material
     respects or if the Issuer 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 existence or happening of any event during the period a Shelf
     Registration Statement is effective which, in the opinion of the Issuer,
     makes any material statement made in such Registration Statement or the
     related Prospectus untrue or which requires the making of any changes in
     such Registration Statement or Prospectus in order to make the statements
     therein not misleading and (vi) of any determination by the Issuer that a
     post-effective amendment to a Registration Statement would be appropriate;

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

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

          (h) in the case of a Shelf Registration, reasonably 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 and enable
     such Registrable Securities to be in such denominations (consistent with
     the provisions of the Indenture) and registered in such names as the
     selling Holders may reasonably request at least one business day prior to
     the closing of any sale of Registrable Securities;

          (i) in the case of a Shelf Registration, upon the occurrence of any
     event contemplated by Section 3(e)(v) hereof, use its reasonable best
     efforts to prepare and file with the SEC a supplement or post-effective
     amendment to a Registration Statement or the related Prospectus or any
     document incorporated therein by reference or file any other


                                       10

<PAGE>

     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 light of the circumstances under which they
     were made, not misleading. The Issuer agrees to notify the Holders to
     suspend use of the Prospectus as promptly as practicable after the
     occurrence of such an event, and the Holders hereby agree to suspend use of
     the Prospectus until the Issuer has amended or supplemented the Prospectus
     to correct such misstatement or omission;

          (j) a reasonable time prior to the filing of any Registration
     Statement, any Prospectus, any amendment to a Registration Statement or
     amendment or supplement to a Prospectus or any document which is to be
     incorporated by reference into a Registration Statement or a Prospectus
     after initial filing of a Registration Statement, provide copies of such
     document to the Initial Purchaser and its counsel (and, in the case of a
     Shelf Registration Statement, the Holders and their counsel) and make such
     of the representatives of the Issuer as shall be reasonably requested by
     the Initial Purchaser or its counsel (and, in the case of a Shelf
     Registration Statement, the Holders or their counsel) available for
     discussion of such document, and shall not at any time file or make any
     amendment to the Registration Statement, any Prospectus or any amendment of
     or supplement to a Registration Statement or a Prospectus or any document
     which is to be incorporated by reference into a Registration Statement or a
     Prospectus, of which the Initial Purchaser and its counsel (and, in the
     case of a Shelf Registration Statement, the Holders and their counsel)
     shall not have previously been advised and furnished a copy or to which the
     Initial Purchaser or its counsel (and, in the case of a Shelf Registration
     Statement, the Holders or their counsel) shall object; provided that this
     Section 3(j) shall not apply to 1934 Act filings made in the ordinary
     course of business;

          (k) obtain a CUSIP number for all Exchange Securities or Registrable
     Securities, as the case may be, not later than the effective date of a
     Registration Statement;

          (l) cause the Indenture to be qualified under the Trust Indenture Act
     of 1939, as amended (the "TIA"), in connection with the registration of the
     Exchange Securities or Registrable Securities, as the case may be,
     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 reasonable
     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) in the case of a Shelf Registration, make available at reasonable
     times and after reasonable notice for inspection by one representative of
     the Holders of the Registrable Securities, any Underwriter participating in
     any disposition pursuant to such Shelf Registration Statement, and
     attorneys and accountants designated by the Holders, at reasonable times
     and in a reasonable manner, all financial and other records, pertinent
     documents and properties of the Issuer and subsidiaries of the Issuer, and
     cause the respective officers, directors and employees of the Issuer to
     supply all information


                                       11

<PAGE>

     reasonably requested by any such representative, Underwriter, attorney or
     accountant in connection with a Shelf Registration Statement;

          (n) in the case of a Shelf Registration, use its reasonable best
     efforts to cause all Registrable Securities to be listed on any securities
     exchange or any automated quotation system on which similar securities
     issued by the Issuer are then listed if requested by the Majority Holders,
     to the extent such Registrable Securities satisfy applicable listing
     requirements;

          (o) use its reasonable best efforts to cause the Exchange Securities
     or Registrable Securities, as the case may be, to be rated by two
     nationally recognized statistical rating organizations (as such term is
     defined in Rule 436(g)(2) under the 1933 Act);

          (p) if reasonably requested by any Holder of Registrable Securities
     covered by a Registration Statement, (i) promptly incorporate in a
     Prospectus supplement or post-effective amendment such information with
     respect to such Holder as such Holder reasonably requests to be included
     therein and (ii) make all required filings of such Prospectus supplement or
     such post-effective amendment as soon as reasonably possible after the
     Issuer has received notification of the matters to be incorporated in such
     filing; and

          (q) in the case of a Shelf Registration, enter into such customary
     agreements and take all such other reasonable actions in connection
     therewith (including those requested by the Holders of a majority of the
     Registrable Securities being sold) in order to expedite or facilitate the
     disposition of such Registrable Securities including, but not limited to,
     an Underwritten Offering and in such connection, (i) to the extent
     possible, make such representations and warranties to the Holders and any
     Underwriters of such Registrable Securities with respect to the business of
     the Issuer and its subsidiaries, the Registration Statement, Prospectus and
     documents incorporated by reference or deemed incorporated by reference, if
     any, in each case, in form, substance and scope as are customarily made by
     issuers to underwriters in underwritten offerings and confirm the same if
     and when requested, (ii) obtain opinions of counsel to the Issuer (which
     counsel and opinions, in form, scope and substance, shall be reasonably
     satisfactory to the 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) obtain "cold comfort" letters from the
     independent certified public accountants of the Issuer (and, if necessary,
     any other certified public accountant of any subsidiary of the Issuer, or
     of any business acquired by the Issuer for which financial statements and
     financial data are or are required to be included in the 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 the Holders of a majority in principal
     amount of the Registrable Securities being sold or the Underwriters, and
     which are customarily delivered in underwritten offerings, to evidence the
     continued validity of the representations and


                                       12

<PAGE>

     warranties of the Issuer made pursuant to clause (i) above and to evidence
     compliance with any customary conditions contained in an underwriting
     agreement.

          In the case of a Shelf Registration Statement, the Issuer may require
each Holder of Registrable Securities to furnish to the Issuer such information
regarding the Holder and the proposed distribution by such Holder of such
Registrable Securities as the Issuer may from time to time reasonably request in
writing.

          In the case of a Shelf Registration Statement, each Holder agrees
that, upon receipt of any notice from the Issuer of the happening of any event
of the kind described in Section 3(e)(v) hereof, such Holder will forthwith
discontinue disposition of Registrable Securities pursuant to a 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 Issuer, such Holder will deliver to the Issuer (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 Issuer shall give any such
notice to suspend the disposition of Registrable Securities pursuant to a Shelf
Registration Statement, the Issuer 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. The Issuer may suspend the disposition of Registrable
Securities pursuant to a Shelf Registration Statement for periods not in excess
of 45 consecutive days and for not more than an aggregate of 90-days in any
12-month period without incurring Additional Interest.

          The Holders of Registrable Securities covered by a 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, subject to the approval of the
Issuer, which approval shall not be unreasonably withheld, condition or delayed.

          4.   Participation of Broker-Dealers in Exchange Offer.

          (a) The Staff of the SEC has taken the position that any broker-dealer
that receives Exchange Securities for its own account in the Exchange Offer in
exchange for Securities that were acquired by such broker-dealer as a result of
market-making or other trading activities (a "Participating Broker-Dealer"), may
be deemed to be an "underwriter" within the meaning of the 1933 Act and must
deliver a prospectus meeting the requirements of the 1933 Act in connection with
any resale of such Exchange Securities.

          The Issuer understands that it is the Staff's position that if the
Prospectus contained in the Exchange Offer Registration Statement includes a
plan of distribution containing a statement to the above effect and the means by
which Participating Broker-Dealers may resell the Exchange Securities, without
naming the Participating Broker-Dealers or specifying the amount of Exchange
Securities owned by them, such Prospectus may be delivered


                                       13

<PAGE>

by Participating Broker-Dealers to satisfy their prospectus delivery obligation
under the 1933 Act in connection with resales of Exchange Securities for their
own accounts, so long as the Prospectus otherwise meets the requirements of the
1933 Act.

          (b) In light of the above, notwithstanding the other provisions of
this Agreement, the Issuer agrees that the provisions of this Agreement as they
relate to a Shelf Registration shall also apply to an Exchange Offer
Registration to the extent, and with such reasonable modifications thereto as
may be, reasonably requested by the Initial Purchaser or by one or more
Participating Broker-Dealers, in each case as provided in clause (ii) below, in
order to expedite or facilitate the disposition of any Exchange Securities by
Participating Broker-Dealers consistent with the positions of the Staff recited
in Section 4(a) above; provided that:

          (i) the Issuer shall not be required to amend or supplement the
     Prospectus contained in the Exchange Offer Registration Statement, as would
     otherwise be contemplated by Section 3(i), for a period exceeding 120 days
     after the last Exchange Date (as such period may be extended pursuant to
     the penultimate paragraph of Section 3 of this Agreement) and Participating
     Broker-Dealers shall not be authorized by the Issuer to deliver and shall
     not deliver such Prospectus after such period in connection with the
     resales contemplated by this Section 4; and

          (ii) the application of the Shelf Registration procedures set forth in
     Section 3 of this Agreement to an Exchange Offer Registration, to the
     extent not required by the positions of the Staff of the SEC or the 1933
     Act and the rules and regulations thereunder, will be in conformity with
     the reasonable request to the Issuer by the Initial Purchaser or with the
     reasonable request in writing to the Issuer by one or more broker-dealers
     who certify to the Initial Purchaser and the Issuer in writing that they
     anticipate that they will be Participating Broker-Dealers; and provided
     further that, in connection with such application of the Shelf Registration
     procedures set forth in Section 3 to an Exchange Offer Registration, the
     Issuer shall be obligated (x) to deal only with one entity representing the
     Participating Broker-Dealers, which shall be Credit Suisse First Boston
     (the "Representative") unless it elects not to act as such representative,
     (y) to pay the fees and expenses of only one counsel representing the
     Participating Broker-Dealers, which shall be counsel to the Initial
     Purchaser unless such counsel elects not to so act and (z) to cause to be
     delivered only one, if any, "cold comfort" letter with respect to the
     Prospectus in the form existing on the last Exchange Date and with respect
     to each subsequent amendment or supplement, if any, effected during the
     period specified in clause (i) above.

          (c) The Initial Purchaser shall have no liability to the Issuer or any
Holder with respect to any request that it may make pursuant to Section 4(b)
above.

          5.   Indemnification and Contribution.

          (a) The Issuer agrees to indemnify and hold harmless the Initial
Purchaser, each Holder and each Person, if any, who controls any Initial
Purchaser or any 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 Holder, from and against all losses, claims,
damages and liabilities (including, without limitation, any legal or other
expenses


                                       14

<PAGE>

reasonably incurred by the Initial Purchaser, any Holder or any such controlling
or affiliated Person 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 any Registration Statement (or any amendment thereto)
pursuant to which Exchange Securities or 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
required to be stated therein or necessary to make the statements therein 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
Issuer shall have furnished any amendments or supplements thereto), 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, 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 the Initial
Purchaser or any Holder furnished to the Issuer in writing through the
Representative or any selling Holder expressly for use therein. In connection
with any Underwritten Offering permitted by Section 3, the Issuer will also
indemnify the Underwriters, if any, selling brokers, dealers and similar
securities industry professionals participating in the distribution, their
officers and directors and each Person who controls such Persons (within the
meaning of the 1933 Act and the 1934 Act) to the same extent as provided above
with respect to the indemnification of the Holders, if requested in connection
with any Registration Statement.

          (b) Each Holder agrees, severally and not jointly, to indemnify and
hold harmless the Issuer, the Initial Purchaser and the other selling Holders,
and each of their respective directors, officers who sign the Registration
Statement and each Person, if any, who controls the Issuer, any Initial
Purchaser and any other selling Holder within the meaning of either Section 15
of the 1933 Act or Section 20 of the 1934 Act to the same extent as the
foregoing indemnity from the Issuer to the Initial Purchaser and the Holders,
but only with reference to information relating to such Holder furnished to the
Issuer in writing by such Holder expressly for use in any 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 either paragraph (a) or paragraph (b) above, such Person (the
"indemnified party") shall promptly notify the Person against whom such
indemnity may be sought (the "indemnifying party") in writing and the
indemnifying party, upon request of the indemnified party, shall retain counsel
reasonably satisfactory to the indemnified party to represent the indemnified
party and any others the indemnifying party 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 party 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 party unless (i) the indemnifying party and the indemnified
party 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 party and the indemnified party and representation of both
parties by the same counsel would be inappropriate due to actual or potential
differing interests between them. It is understood that the indemnifying party
shall not, in connection with any proceeding or related proceedings in the same
jurisdiction, be liable for (a) the fees and expenses of more than one


                                       15

<PAGE>

separate firm (in addition to any local counsel) for the Initial Purchaser and
all Persons, if any, who control any Initial Purchaser within the meaning of
either Section 15 of the 1933 Act or Section 20 of the 1934 Act, (b) the fees
and expenses of more than one separate firm (in addition to any local counsel)
for the Issuer, its directors, its officers who sign the Registration Statement
and each Person, if any, who controls the Issuer within the meaning of either
such Section and (c) the fees and expenses of more than one separate firm (in
addition to any local counsel) for all Holders and all Persons, if any, who
control any Holders within the meaning of either such Section, and that all such
fees and expenses shall be reimbursed as they are incurred. In such case
involving the Initial Purchaser and Persons who control the Initial Purchaser,
such firm shall be designated in writing by the Representative. In such case
involving the Holders and such Persons who control Holders, such firm shall be
designated in writing by the Majority Holders. In all other cases, such firm
shall be designated by the Issuer. The indemnifying party 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 party agrees to indemnify the indemnified party from and
against any loss or liability by reason of such settlement or judgment.
Notwithstanding the foregoing sentence, if at any time an indemnified party
shall have requested an indemnifying party to reimburse the indemnified party
for fees and expenses of counsel as contemplated by the second and third
sentences of this paragraph, the indemnifying party agrees that it shall be
liable for any settlement of any proceeding effected without its written consent
if (i) such settlement is entered into more than 30 days after receipt by such
indemnifying party of the aforesaid request and (ii) such indemnifying party
shall not have reimbursed the indemnified party for such fees and expenses of
counsel in accordance with such request prior to the date of such settlement. No
indemnifying party shall, without the prior written consent of the indemnified
party, effect any settlement of any pending or threatened proceeding in respect
of which such indemnified party is or could have been a party and indemnity
could have been sought hereunder by such indemnified party, unless such
settlement includes an unconditional release of such indemnified party from all
liability on claims that are the subject matter of such proceeding.

          (d) If the indemnification provided for in paragraph (a) or paragraph
(b) of this Section 5 is unavailable to an indemnified party or insufficient in
respect of any losses, claims, damages or liabilities, then each indemnifying
party under such paragraph, in lieu of indemnifying such indemnified party
thereunder, shall contribute to the amount paid or payable by such indemnified
party as a result of such losses, claims, damages or liabilities in such
proportion as is appropriate to reflect the relative fault of the indemnifying
party or parties on the one hand and of the indemnified party or parties 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. The relative fault of the Issuer and the Holders shall be
determined by reference to, among other things, whether the untrue or alleged
untrue statement of a material fact or the omission or alleged omission to state
a material fact relates to information supplied by the Issuer or by the Holders
and the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent such statement or omission. The Holders'
respective obligations to contribute pursuant to this Section 5(d) are several
in proportion to the respective principal amount of Registrable Securities of
such Holder that were registered pursuant to a Registration Statement.


                                       16

<PAGE>

          (e) The Issuer and each Holder agree that it would not be just or
equitable if contribution pursuant to this Section 5 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 paragraph (d) above. The amount paid
or payable by an indemnified party as a result of the losses, claims, damages
and liabilities referred to in paragraph (d) above shall be deemed to include,
subject to the limitations set forth above, any legal or other expenses
reasonably incurred by such indemnified party in connection with investigating
or defending any such action or claim. Notwithstanding the provisions of this
Section 5, no Holder shall be required to indemnify or 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 remedies provided for in this Section 5 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.

          The indemnity and contribution provisions contained in this Section 5
shall remain operative and in full force and effect regardless of (i) any
termination of this Agreement, (ii) any investigation made by or on behalf of
the Initial Purchaser, any Holder or any Person controlling any Initial
Purchaser or any Holder, or by or on behalf of the Issuer, its officers or
directors or any Person controlling the Issuer, (iii) acceptance of any of the
Exchange Securities and (iv) any sale of Registrable Securities pursuant to a
Shelf Registration Statement.

          6.   Miscellaneous.

          (a) No Inconsistent Agreements. The Issuer 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 Issuer'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 Issuer 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 5
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
first-class mail, telex, telecopier, or any courier guaranteeing overnight
delivery (i) if to a Holder, at the most current address given by such Holder to
the Issuer by means of a notice given in accordance with the provisions of this
Section 6(c), which address initially is, with respect to the Initial Purchaser,
the address


                                       17

<PAGE>

set forth in the Purchase Agreement; and (ii) if to the Issuer, initially at the
Issuer'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 6(c).

          All such notices and communications shall be deemed to have been duly
given: at the time delivered by hand, if personally delivered; five business
days after being deposited in the mail, postage prepaid, if mailed; when
answered back, if telexed; when receipt is acknowledged, if telecopied; and on
the next business day if timely delivered to an air courier guaranteeing
overnight delivery.

          Copies of all such notices, demands, or other communications shall be
concurrently delivered by the Person giving the same to the Trustee, at the
address specified in the Indenture.

          (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 an express
assignment, 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. 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 receive the benefits hereof. The Initial Purchaser
(in their capacity as Initial Purchaser) shall have no liability or obligation
to the Issuer with respect to any failure by a Holder to comply with, or any
breach by any Holder of, any of the obligations of such Holder under this
Agreement.

          (e) Purchases and Sales of Securities. During the period of two years
after the Closing Date, the Issuer will not resell any of the Securities which
constitute "restricted securities" under Rule 144 that it has reacquired, unless
the Securities are resold in a transaction registered under the 1933 Act.

          (f) Third-Party Beneficiary. The Holders shall be third-party
beneficiaries to the agreements made hereunder between the Issuer, on the one
hand, and the Initial Purchaser, 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 executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

          (h) Headings. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

          (i) Governing Law. This Agreement shall be governed by the laws of the
State of New York.


                                       18

<PAGE>

          (j) Severability. In the event that any one or more of the provisions
contained herein, or the application thereof in any circumstance, 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.


                                       19

<PAGE>

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

                                   CENTENNIAL COMMUNICATIONS CORP.


                                   By /s/ Tony L. Wolk
                                      ------------------------------------------
                                   Name: Tony L. Wolk
                                         ---------------------------------------
                                   Title: Senior Vice President, General Counsel
                                          --------------------------------------


                                       20

<PAGE>

Confirmed and accepted as of the date
first above written:

By: CREDIT SUISSE FIRST BOSTON LLC


By /s/ Michael Speller
   ----------------------------------
Name: Michael Speller
      -------------------------------
Title: Director
       ------------------------------


                                       21