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                                                                    EXHIBIT 4.51

              CONTRACT RELATING TO THE EXCLUSIVE PURCHASE RIGHT OF
                                 EQUITY INTEREST

                                      AMONG

                                  LINKTONE LTD.

                                       AND

                                   WANG WENLEI

                                       AND

                       SHANGHAI WEILAN COMPUTER CO., LTD.

                          DATED AS OF OCTOBER 16, 2006

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                              CONTRACT RELATING TO
               THE EXCLUSIVE PURCHASE RIGHT OF AN EQUITY INTEREST

     Contract Relating to the Exclusive Purchase Right of An Equity Interest,
dated as of October 16, 2006 (this "Contract"), among:

     (1)  Linktone Ltd. (the "Lender"), a limited company established and
          registered in Cayman island, with the address at Cayman islands in
          British West Indies

     (2)  Wang Wenlei, Resident of the People's Republic of China (the "PRC"),
          holding the Identification Card of the PRC (No. 310109197303083227),
          with the address at Room 502, No.50, Lane 471, Miyun Road, Hongkou
          District, Shanghai (the "Party B"); and

     (3)  Shanghai Weilan Computer Co., Ltd., a limited liability company
          organized and existing under the laws of the PRC, with the legal
          registration address at No.558 Dazhi West Road, Malu Town Jiading
          District (the Party "C").

     As used in this Contract, Party A, Party B, and Party C is "the Party"
     respectively, and "Parties to the Contract" in all.

     WHEREAS,

     1.   Party B has the ownership of 50% equity interest in Party C.

     2.   Party A and Party B entered into a loan agreement dated October 16,
          2006 ("the Loan Agreements").

     3.   Party C and Linktone Consulting Limited Shanghai, a wholly owned
          subsidiary company of Party A, entered into a series of contracts such
          as Exclusive Technical Consulting and Services Agreement Contracts.

NOW, THEREFORE, the parties to this Contract hereby agree as follows:

1.   PURCHASE AND SALE OF EQUITY INTEREST

1.1  Authorization

     Party B hereby irrevocably delivers to Party A, under the laws of the PRC,
an irrevocable sole authority ("Purchase Right of Equity Interest") of,
following the steps decided by Party A, and the price specified in Section 1.3
of this Contract, purchasing by Party A or by one or more persons designated by
Party A (the "Designated Persons") at any time from Party B of its all or part
of the equity interest of Party C. Besides Party A and the Designated Persons,
any third party does not have such Purchase Right of Equity Interest. Party C
hereby agrees the delivery of Purchase Right of Equity Interest from Party B to
Party A. As specified

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in this Section and this Contract, the "person" has the meaning of Person,
Corporation, Joint Venture, Partnership, Enterprise, Trust or Non-Corporation
Organization.

1.2  Steps

       The performance of Purchase Right of Equity Interest of Party A shall be
upon and subject to the laws and regulations of PRC. Party A shall send a
written notice (the "Notice of Purchase of Equity Interest") to Party B upon its
performance of Purchase Right of Equity Interest, the Notice of Purchase of
Equity Interest shall have in it the following contents:

     (a)  Party A's decision of the performance of purchase right;

     (b)  The Equity Interest prospected to be purchased by Party A from Party B
          (the "Purchased Equity Interest");

     (c)  Purchase Date/Equity Interest Transferring Date.

1.3  Purchase Price

Except as requested by law to evaluate, the price of the Purchased Equity
Interest ("Purchase Price") shall be an equivalent of the actual amount of the
Purchased Equity Interest contributed by Party B.

1.4  Transfer of the Purchased Equity Interest

Every time upon Party A's performance of the Purchase Right of Equity Interest:

(1)  Party B shall supervise and urge Party C to convene the shareholders
     meeting, and during the meeting, to pass the decision or resolution to
     transfer the equity interest from Party B to Party A and/or the Designated
     Persons;

(2)  Party B shall, upon the terms and conditions of this Contract and the
     Notice of Purchase of Equity Interest, enter into Equity Interest Transfer
     Contract with Party A (or, in applicable situation, the Designated
     Persons);

(3)  The related parties shall execute all other requisite contracts, agreements
     or documents, acquire all requisite approval and consent of the government,
     and, without any security interest, perform all requisite action to
     transfer the valid ownership of the Purchased Equity Interest to Party A
     and/or the Designated Person, and to cause Party A and/or the Designated
     Person to be the registered owner of the Purchased Equity Interest. For
     this Section and this Contract, "Security Interest" has the meaning of
     security, mortgage, right or interest of the third party, any purchase
     right of equity interest, right of acquisition, prior purchase right, right
     of set-off, ownership detainment or other security arrangements. To further
     define the meaning, it does not include any security interest subject to
     this Contract or the equity interest pledge contract of Party B. As
     described in this Section and this Contract, "the Equity Interest Pledge

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     Contract of Party B" has the meaning of the Equity Interest Pledge Contract
     entered into by Linktone Consulting Limited Shanghai. and Party B dated as
     of the execution date of this Contract. According to the said Contract, to
     secure Party C to perform the obligations subject to the Exclusive
     Technology Consulting and Service Agreement entered into between Party C
     and Linktone Consulting Limited Shanghai, Party B pledges all its equity
     interest in Party C to Linktone Consulting Limited Shanghai.

1.5  Payment

Whereas contemplated in the Loan Contract, any proceeds gained by Party B from
the transfer of its equity interest in Party C shall be used, according to the
Loan Contract, as the payment to its loan borrowed from Party A. Therefore, upon
the performance of the Purchase Right of Equity Interest by Party A, the
Purchase Price shall be used as the payment from Party B to Party A subject to
the loan. Party A does not need pay the Purchase Price to Party B anymore.

2.   PROMISES RELATING EQUITY INTEREST

2.1  Promises Relating Party C

Party C hereby promises:

(1)  Without prior written consent by Party A or Linktone Consulting Limited
     Shanghai., Ltd., Party A's Affiliate in PRC, not, in any form, to
     complement, change or renew the Articles of the Association of Party C, to
     increase or decrease registered capital of the corporation, or to change
     the structure of the registered capital in any other forms;

(2)  Following kind finance and business standard and tradition, to maintain the
     exist of the corporation, prudently and effectively operate business and
     process affairs;

(3)  Without prior written consent by Party A or Linktone Consulting Limited
     Shanghai, Party A's Affiliate in PRC, not, dated from the execution date of
     this Contract, to sale, transfer, mortgage or dispose in any other form any
     assets, legitimate or beneficial interest of business or income of Party C,
     or to approve any other security interest set on it;

(4)  Without prior written notice by Party A, no debt shall take place, be
     inherited, be guaranteed, or be allowed to exist, with the exception of:
     (i) debt from normal or daily business but not from borrowing; (ii) debt
     having been disclosed to Party A or having gained written consent from
     Party A;

(5)  To normally operate all business to maintain the asset value of Party C,
     without doing or otherwise any action that sufficiently affects the
     operation and asset value;

(6)  Without prior written consent by Party A or Linktone Consulting Limited
     Shanghai, Party A's Affiliate in PRC, not to enter into any material
     contract, with

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     the exception of the contract entered into during the normal business (As
     in this paragraph, a contract with a value more than 5 hundred thousand
     Yuan (RMB 500,000) shall be seemed as a material contract);

(7)  Without prior written consent by Party A or Linktone Consulting Limited
     Shanghai, Party A's Affiliate in PRC, not to provide loan or credit loan to
     anyone;

(8)  Upon the request of Party A, to provide all operation and finance materials
     relevant to Party C;

(9)  Party C purchases and holds all along insurance from the insurance company
     accepted by Party A, the insurance amount and category shall be the same
     with those held by the companies in the same area, operating the similar
     business and owning the similar properties and assets;

(10) Without prior written consent by Party A or Linktone Consulting Limited
     Shanghai, Party A's Affiliate in PRC, not to merger or associate with any
     person, or purchase any Person or invest in any Person;

(11) To notify Party A the occurrence or the probable occurrence of the
     litigation, arbitration or administrative procedure related to the assets,
     business and income of Party C;

(12) In order to keep the ownership of Party C to all its assets, to execute all
     requisite or appropriate documents, do all requisite or appropriate action,
     and advance all requisite or appropriate accusation, or make requisite or
     appropriate plea for all claims;

(13) Without prior written notice by Party A, not to assign stock interests to
     shareholders in any form, but upon the request of Party A, to assign all
     its assignable profits to their own shareholders;

(14) Upon the request of Linktone Consulting Limited Shanghai, Party A's
     Affiliate in PRC, to commission any person designated by Linktone
     Consulting Limited Shanghai to be the member of the Board of Directors of
     Party C; and

2.2  Promises Relating Party B

Party B promises:

(1)  Without prior written consent by Party A or Linktone Consulting Limited
     Shanghai, Party A's Affiliate in PRC, not, dated from the execution date of
     this Contract, to sale, transfer, mortgage or dispose in any other form any
     legitimate or beneficial interest of equity interest, or to approve any
     other security interest set on it, with the exception of the pledge set on
     the equity interest of Party B subject to Equity Interest Pledge Contract
     of Party B;

(2)  To cause the Board of Shareholders commissioned by it not to approve to,
     with no prior written notice by Party A or Linktone Consulting Limited
     Shanghai., Party A's Affiliate in PRC, and dated from the execution date of
     this Contract, sale, transfer, mortgage or dispose in any other form any
     legitimate or beneficial interest of equity interest, or to approve any
     other security interest set on it, with the exception of the pledge set on
     the equity interest of Party B subject to Equity

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     Interest Pledge Contract of Party B;

(3)  To cause the Board of Shareholders commissioned by it not to approve Party
     C to, with no prior written notice by Party A or Linktone Consulting
     Limited Shanghai., Party A's Affiliate in PRC, merger or associate with any
     person, or purchase any person or invest in any person;

(4)  To notify Party A the occurrence or the probable occurrence of the
     litigation, arbitration or administrative procedure related to the equity
     interest owned by it;

(5)  To cause the Board of Shareholders commissioned by it to vote to approve
     the transfer of the Purchased Equity Interest subject to this Contract;

(6)  In order to keep its ownership of the equity interest, to execute all
     requisite or appropriate documents, do all requisite or appropriate action,
     and advance all requisite or appropriate accusation, or make requisite or
     appropriate plea for all claims;

(7)  Upon the request of Linktone Consulting Limited Shanghai, Party A's
     Affiliate in PRC, to commission any person designated by Linktone
     Consulting Limited Shanghai to be the member of the Board of Directors of
     Party C;

(8)  Upon the request of Party A at any time, to immediately transfer its equity
     interest to the representative designated by Party A unconditionally or
     abandon its first refusal right of equity interest transferring from
     another current shareholder to Party A or other people designated by Party
     A;

(9)  To prudently comply with the terms and conditions of this Contract and
     other contracts entered into totally or respectively by Party B, Party C
     and Party A and Linktone Consulting Limited Shanghai, to actually perform
     all obligations under these contracts, without doing or otherwise any
     action that sufficiently affects the validity and enforceability of these
     contracts;

3.   REPRESENTATIONS AND WARRANTIES

Representations and Warranties of Party B and Party C

Dated as of the execution date of this Contract and every transferring date,
Party B and Party C hereby represents and warrants together and respectively to
Party A as follows:

(1)  It has the power and ability to enter into and deliver this Contract, and
     any equity interest transferring contract ("Transferring Contract",
     respectively) having it as a party, for every single transfer of the
     purchased equity interest according to this Contract, and to perform its
     obligations under this Contract and any Transferring Contract. Upon
     execution, this Contract and the Transferring Contracts having it as a
     party constitute a legal, valid and binding obligation of it enforceable
     against it in accordance with its terms;

(2)  The execution, delivery of this Contract and any Transferring Contract and
     performance of the obligations under this Contract and any Transferring
     Contract do not: (i) cause to violate any relevant laws of PRC; (ii)
     constitute a conflict with

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     its Articles of Association or other organizational documents; (iii) cause
     to breach any contract or instruments to which it is a party or having
     binding obligation on it, or cause to breach any contract or instruments to
     which it is a party or having binding obligation on it; (iv) cause to
     violate relevant authorization of any consent or approval to it and/or any
     continuing valid condition; or (v) cause any consent or approval authorized
     to it to be suspended, removed, or into which other requests be added;

(3)  Party C bears the kind and sellable ownership of all assets. Party C does
     not set any security interest on the said assets;

(4)  Party C does not have any undischarged debt, with the exception of (i) debt
     from its normal business; and (ii) debt having been disclosed to Party A
     and having gained written consent from Party A;

(5)  Party C abides by all laws and regulations applicable to the purchase of
     assets;

(6)  No litigation, arbitration or administrative procedure relating to equity
     interest, assets of Party C or the corporation is underway or to be decided
     or to probably take place;

4.   EFFECTIVE DATE

     This Contract shall be effectively dated from the execution date, with the
     term of effect as 10 years, and can be extended to another 10 years by the
     choice of Party A.

5.   APPLICABLE LAW AND DISPUTE RESOLUTION

5.1  Applicable Law

The execution, validity, construing and performance of this Contract, and
resolution of the disputes under this Contract, shall be in accordance with the
laws of PRC.

5.2  Dispute Resolution

Any dispute arising from the construing and performance of this Contract shall
be settled through friendly consultation between the parties of this Contract.
If no settlement can be reached through such consultation within thirty (30)
days after the date of the written notice sent by one party to the other
requesting to settle the dispute, then each of the parties shall have the right
to refer the matter to China International Economic and Trade Arbitration
Commission, for settlement by arbitration according to the its valid arbitration
rules at the appointed time. The arbitration shall take place in Shanghai. The
arbitration result is final, and is binding to both parties of this Contract.

6.   TAXES AND EXPENSES

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Every party shall, according to laws of PRC, bear any and all transferring and
registering taxes, costs and expenses for the preparation and execution of this
Contract and all Transferring Contracts, and those arising from or imposed on
the party, to complete the transactions of this Contract and all Transferring
Contracts.

7.   NOTICES

This Contract requests that notices or other communications sent by any party or
corporation shall be written in Chinese, and be delivered in person, by mail or
telecopy to other parties at the following addresses or other specified
addresses noticed by other parties to the party. The date deemed to be duly
given or made shall be confirmed as follows: (a) for notices delivered in
person, the date of delivery shall be deemed as having been duly given or made;
(b) for notices delivered by mail, the tenth day of the delivery date of air
certified mail with postage prepaid (as shown on stamp) shall be deemed as
having been duly given or made; and (c) for notices by telecopy, the receipt
date showed on the delivery confirming paper of the relevant document shall be
deemed as having been duly given or made.

Party A:       Linktone Ltd
Address:       Cayman Islands, British West indies
Tel:           ___________________
Facsimile No.: ___________________

Party B:       Wang Wenlei
Address:       Room 402 No.108, the 8th Community of Sitang, Baoshan District,
               Shanghai

Party C:       Shanghai Weilan Computer Co., Ltd.
Address:       No.558 Dazhi West Road, Malu Town Jiading District
Facsimile No.: ___________________
Tel:           ___________________

8.   CONFIDENTIALITY

Both the parties admit and confirm any oral or written materials exchanged by
the parties relating to this Contract are confidential. Both parties shall
maintain the secrecy and confidentiality of all such materials. Without written
approval by the other party, the party shall not disclose to ay third party any
relevant materials, but with the exception of the following: (a) the public know
or may know such materials (but not disclosed by the party accepting the
materials); (b) materials needed to be disclosed subject to ordinance or listing
rules or precedents of the united transaction firm; or (c) any party necessarily
discloses materials to its legal or financial consultant relating the
transaction of this Contract, and this legal or financial consultant shall have
the obligation of confidentiality similar to that set forth in this Section. The

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breach of the obligation of confidentiality by staff or employed institution of
any party shall be deemed as the breach of such obligation by that party, and by
whom the liabilities for breach shall be bored. No matter this Contract may
terminate by any reason, this Section shall continue in force and effect.

9.   FURTHER WARRANTIES

The Parties to the Contract agree to promptly execute documents reasonably
requisite to the performance of the provisions and the aim of this Contract or
documents beneficial to it, and to take actions reasonably requisite to the
performance of the provisions and the aim of this Contract or actions beneficial
to it.

10.  MISCELLANEOUS

10.1 Amendment, Modification and Supplement

Upon amendment, modification and supplement of this Contract shall be subject to
the written agreement executed by each party.

10.2 Observance of Laws and Regulations

The parties of the contract shall observe and make sure the operation of each
party fully observe all laws and regulations of PRC officially published and
publicly gainable.

10.3 Entire Contract

Except the written amendment, supplement and modification of this Contract
following the date of execution, this contract and attachments 1 constitute the
entire contract of the parties hereto with respect to the object hereof and
supersedes all prior oral or written agreements, representation and contracts
with respect to the object hereof.

10.4 Headings

The headings contained in this Contract are for convenience of reference only
and shall not affect the interpretation, explanation or in any other way the
meaning of the provisions of this Contract.

10.5 Language

This Contract is written in Chinese, and the three copies are in the same form.

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10.6 Separability

If any one or more provisions of this Contract are judged as invalid, illegal or
non-enforceable in any way according to any laws or regulations, the validity,
legality and enforceability of other provisions hereof shall not be affected or
impaired in any way. All parties shall, through sincere consultation, urge to
replace those invalid, illegal or non-enforceable provisions with valid ones,
and from such valid provisions, similar economic effects shall be tried to reach
as from those invalid, illegal or non-enforceable provisions.

10,7 Successor

This Contract shall bind and benefit the successor of each party and the
transferee allowed by each party.

10.8 Survival

(a)  Any obligation taking place or at term hereof prior to the end or
     termination ahead of the end of this Contract shall continue in force and
     effect notwithstanding the occurrence of the end or termination ahead of
     the end of the Contract.

(b)  Section 5, Section7 and Section 10.8 hereof shall continue in force and
     effect after the termination of this Contract.

10.9 Waiver

Any party to this Contract may waive the terms and conditions of this Contract.
Such waiver shall be valid only if set forth in an instrument in writing signed
by the party or parties to be bound thereby. Any waiver by a party to the breach
hereof by other parties in certain situation shall not be construed as a waiver
to any similar breach by other parties in other situation.

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IN WITNESS THEREFORE, the parties hereof have caused this Contract to be
executed by their duly authorized representatives as of the date first written
above.

Party A: Linktone Ltd.


By:               [seal]
    ---------------------------------
Name:
      -------------------------------
Title:
       ------------------------------


Party B: Wang Wenlei (ID Card No.:310109197303083227)


By:            [signature]
    ---------------------------------
Name: Wang Wen Lei


Party C: Shanghai Weilan Computer Co., Ltd.


By:               [seal]
    ---------------------------------
Name:
      -------------------------------
Title:
       ------------------------------