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                                                                    EXHIBIT 4.57

                        EQUITY INTERESTS PLEDGE AGREEMENT

This Equity Interests Pledge Agreement is entered into on the day of April 1,
2006 in Shanghai, the People's Republic of China (hereinafter referred to as the
"PRC") by and between the following parties:

Pledgee:       Shanghai Huitong Information Co., Ltd.
Address:       No.28, Jiaji Road, Jiading District, Shanghai

Pledgor:       Zhangrong
Identity Code: 310103197503303222
Address:       Room 403 No. 7 Shaoxing Road, Luwan District, Shanghai

WHEREAS,

1.   Zhangrong, the Pledgor, is a citizen of the PRC. The Pledgor owns 50% of
     the equity interest in Shanghai Unilink Computer Co., Ltd. ("Shanghai
     Unlink") Shanghai Unlink is a limited liability company registered in
     Shanghai, the PRC.

2.   The Pledgee, a wholly foreign-owned company registered in Shanghai, the
     PRC, has been licensed by the PRC relevant government authority to carry on
     the business of Internet technical service. The Pledgee and the
     Pledgor-owned Shanghai Unlink enter into Exclusive Technical Consulting and
     Services Agreement (the "Service Agreement") on __________.

3.   In order to make sure that the Pledgee collect technical service fees as
     normal from Shanghai Unlink, the Pledgor is willing to pledge all its
     equity interest in Shanghai Unlink to the Pledgee as a security for the
     Pledgee to collect technical consulting and service fees under the Service
     Agreement;

     In order to define each Party's rights and obligations, the Pledgee and the
     Pledgor through mutual negotiations hereby enter into this Agreement based
     upon the following terms:

1.   Definitions

Unless otherwise provided in this Agreement, the following terms shall have the
following meanings:

     1.1  Pledge means the full content of Article 2 hereunder

     1.2  Equity Interest means all 50% equity interests in Shanghai Unlink
          legally held by the Pledgor.


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     1.3  Rate of Pledge means the ratio between the value of the pledge under
          this Agreement and the exclusive technical consulting and service fees
          under the Service Agreement.

     1.4  Term of Pledge means the period provided for under Article 3.2
          hereunder.

     1.5  Service Agreement means the Exclusive Technical Consulting and Service
          Agreement entered into by and between Shanghai Unlink and the Pledgee
          on ________.

     1.6  Event of Default means any event in accordance with Article 7
          hereunder.

     1.7  Notice of Default means the notice of default issued by the Pledgee in
          accordance with this Agreement.

2.   Assignment And Pledge

     2.1  The Pledgor agrees to pledge all its equity interest in Shanghai
          Unlink to the Pledgee.

     2.2  Pledge under this Agreement refers to the rights owned by the Pledgee
          who shall be entitled to have priority in receiving payment by the
          evaluation or proceeds from the auction or sale of the equity
          interests pledged by the Pledgor to the Pledgee.

3.   Rate Of Pledge And Term Of Pledge

     3.1  The rate of Pledge

          3.1.1 The rate of pledge shall be 100%

     3.2  The term of Pledge

          3.2.1 Pledge Contract shall take effect as of the date when the equity
               interests under this Agreement are recorded in the Register of
               Shareholder of Shanghai Unlink and registered with the competent
               Administration for Industry and Commerce. The term of the Pledge
               is the same with the term of Service Agreement.

          3.2.2 During the Pledge, the Pledgor shall be entitled to dispose the
               Pledge in accordance with this Agreement in the event that
               Shanghai Unlink fails to pay exclusive technical Consulting and
               service fee in accordance with the Service Agreement.


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4.   Physical Possession Of Documents

     4.1  During the term of Pledge under this Agreement, the Pledgor shall
          deliver the physical possession of the Certificate of Distribution and
          the Name List of Shareholder of Shanghai Unlink to the Pledgee within
          one week as of the date of execution of this Agreement.

     4.2  The Pledgee shall be entitled to collect the dividends from the equity
          interests.

5.   Warranties And Representation Of The Pledgor

     5.1  The Pledgor is the legal owner of the equity interests.

     5.2  The Pledgee shall not be interfered by any other the Pledgee at any
          time once Party exercises the rights of the Pledgee in accordance with
          this Agreement.

     5.3  The Pledgee shall be entitled to dispose or assign the pledge in
          accordance with this Agreement.

     5.4  The Pledgor does not pledge or encumber the equity interests to any
          other person except for the Pledgee.

6.   Covenant Of The Pledgor

     6.1  During the effective term of this Agreement, the Pledgor covenants to
          the Pledgee that the Pledgor shall:

          6.1.1 Except the transfer of equity interest, as subject to the
               Exclusive Purchase Right Contract entered into among the Pledgor,
               Linktone Ltd. and Shanghai Unlink on ______, to Linktone Ltd. or
               the person designated by Linktone Ltd., not transfer or assign
               the equity interests, create or permit to create any pledges
               which may have an adverse effect on the rights or benefits of the
               Pledgee without prior written consent from the Pledgee;

          6.1.2 comply with and implement laws and regulations with respect to
               the pledge of rights, present to the Pledgee the notices, orders
               or suggestions with respect to the Pledge issued or made by the
               competent authority within five days upon receiving such notices,
               orders or suggestions and comply with such notices, orders or
               suggestions, or object to the foregoing matters at the reasonable


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               request of the Pledgee or with consent from the Pledgee.

          6.1.3 timely notify the Pledgee of any events or any received notices
               which may affect the Pledgor's equity interest or any part of its
               right, and any events or any received notices which may change
               the Pledgor's any covenant and obligation under this Agreement or
               which may affect the Pledgor's performance of its obligations
               under this Agreement.

     6.2  The Pledgor agrees that the Pledgee's right of exercising the Pledge
          obtained from this Agreement shall not be suspended or hampered
          through legal procedure by the Pledgor or any successors of the
          Pledgor or any person authorized by the Pledgor or any other person.

     6.3  The Pledgor warrants to the Pledgee that in order to protect or
          perfect the security over the payment of the technical consulting and
          service fees under the Service Agreement, the Pledgor shall execute in
          good faith and cause other parties who have interests in the pledge to
          execute all the title certificates, contracts, and or perform and
          cause other parties who have interests to take action as required by
          the Pledgee and make access to exercise the rights and authorization
          vested in the Pledgee under this Agreement, and execute all the
          documents with respect to the changes of certificate of equity
          interests with the Pledgee or the person(natural person or legal
          entity) designed by the Pledgee, and provides all the notices, orders
          and decisions regarded as necessary by the Pledgee with the Pledgee
          within the reasonable time.

     6.4  The Pledgor warrants to the Pledgee that the Pledgor will comply with
          and perform all the guarantees, covenants, agreements, representations
          and conditions for the benefits of the Pledgee. The Pledgor shall
          compensate all the losses suffered by the Pledgee for the reasons that
          the Pledgor does not perform or fully perform their guarantees,
          covenants, agreements, representations and conditions.

7.   Event Of Default

     7.1  The following events shall be regarded as the event of default:

          7.1.1 Shanghai Unlink fails to make full payment of the exclusive
               technical consulting and service fees as scheduled under the
               Service Agreement;

          7.1.2 The Pledgor makes any material misleading or fraudulent
               representations or warranties under Article 5 herein, and/or the


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               Pledgor is in violation of any warranties under Article 5 herein;

          7.1.3 The Pledgor violates the covenants under Article 6 herein;

          7.1.4 The Pledgor violates any terms and conditions herein;

          7.1.5 Except provided otherwise in Article 6.1.1 herein, the Pledgor
               waives the pledged equity interests or transfers or assigns the
               pledged equity interests without prior written consent from the
               Pledgee;

          7.1.6 The Pledgor's any external loan, security, compensation,
               covenants or any other compensation liabilities (1) are required
               to be repaid or performed prior to the scheduled date; or (2) are
               due but can not be repaid or performed as scheduled and thereby
               cause the Pledgee to deem that the Pledgor's capacity to perform
               the obligations herein is affected;

          7.1.7 The Pledgor is incapable of repaying the general debt or other
               debt;

          7.1.8 This Agreement is illegal for the reason of the promulgation of
               the related laws or the Pledgor's incapability of continuing to
               perform the obligations herein;

          7.1.9 Any approval, permits, licenses or authorization from the
               competent authority of the government needed to perform this
               Agreement or validate this Agreement are withdrawn, suspended,
               invalidated or materially amended;

          7.1.10 The property of the Pledgor is adversely changed and cause the
               Pledgee deem that the capability of the Pledgor to perform the
               obligations herein is affected;

          7.1.11 The successors or assignees of the Shanghai Unlink are only
               entitled to perform a portion of or refuse to perform the payment
               liability under the Service Agreement;

          7.1.12 Other circumstances whereby the Pledgee is incapable of
               exercising the right to dispose the Pledge in accordance with the
               related laws.

     7.2  The Pledgor shall immediately give a written notice to the Pledgee if
          the Pledgor is aware of or find that any event under Article 7.1
          herein or any events that may result in the foregoing events have
          happened or is going on.


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     7.3  Unless the event of default under Article 7.1 herein has been solved
          to the Pledgee's satisfaction, the Pledgee, at any time when the event
          of default happens or thereafter, may give a written notice of default
          to the Pledgor and require the Pledgor to immediately make full
          payment of the outstanding service feess under the Service Agreement
          and other payables or dispose the Pledge in accordance with Article 8
          herein.

8.   Exercise Of The Right Of The Pledge

     8.1  The Pledgor shall not transfer or assign the pledge without prior
          written approval from the Pledgee prior to the full repayment of the
          consulting and service fee under the Service Agreement.

     8.2  The Pledgee shall give a notice of default to the Pledgor when the
          Pledgee exercises the right of pledge.

     8.3  Subject to Article 7.3, the Pledgee may exercise the right to dispose
          the Pledge at any time when the Pledgee gives a notice of default in
          accordance with Article 7.3 or thereafter.

     8.4  The Pledgee is entitled to have priority in receiving payment by the
          evaluation or proceeds from the auction or sale of whole or part of
          the equity interests pledged herein in accordance with legal procedure
          until the outstanding consulting and service fees and all other
          payables under the Service Agreement are repaid.

     8.5  The Pledgor shall not hinder the Pledgee from disposing the Pledge in
          accordance with this Agreement and shall give necessary assistance so
          that the Pledgee could realize his Pledge.

9.   Transfer Or Assignment

     9.1  The Pledgor shall not donate or transfer his rights and obligations
          herein without prior consent from the Pledgee.

     9.2  This Agreement shall be binding upon the Pledgor and his successors
          and be effective to the Pledgee and his each successor and assignee.

     9.3  The Pledgee may transfer or assign his all or any rights and
          obligations under the Service Agreement to any individual (natural
          person or legal entity) at any time. In this case, the assignee shall
          enjoy and undertake the same rights and obligations herein of the
          Pledgee as if the assignee is a party hereto. When the Pledgee
          transfers or assigns the rights and obligations under the Service
          Agreement, at the request of the Pledgee, the


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          Pledgor shall execute the relevant agreements and/or documents with
          respect to such transfer or assignment.

     9.4  After the Pledgee's change resulting from the transfer or assignment,
          the new parties to the pledge shall reexecute a pledge contract.

10.  Termination

This Agreement shall not be terminated until the consulting and service fees
under the Service Agreement are paid off and the Shanghai Unlink will not
undertake any obligations under the Service Agreement any more, and the Pledgee
shall cancel or terminate this Agreement within reasonable time as soon as
practicable.

11.  Formalities Fees And Other Charges

     11.1 The Pledgor shall be responsible for all the fees and actual
          expenditures in relation to this Agreement including but not limited
          to legal fees, cost of production, stamp tax and any other taxes and
          charges. If the Pledgee pays the relevant taxes in accordance with the
          laws, the Pledgor shall fully indemnify such taxes paid by the
          Pledgee.

     11.2 The Pledgor shall be responsible for all the fees (including but not
          limited to any taxes, formalities fees, management fees, litigation
          fees, attorney's fees, and various insurance premiums in connection
          with disposition of Pledge) incurred by the Pledgor for the reason
          that (1) The Pledgor fails to pay any payable taxes, fees or charges
          in accordance with this Agreement; or (2) The Pledgee has recourse to
          any foregoing taxes, charges or fees by any means for other reasons.

12.  Force Majeure

     12.1 If this Agreement is delayed in or prevented from performing in the
          Event of Force Majeure ("Event of Force Majeure"), only within the
          limitation of such delay or prevention, the affected party is absolved
          from any liability under this Agreement. Force Majeure, which includes
          acts of governments, acts of nature, fire, explosion, typhoon, flood,
          earthquake, tide, lightning, war, means any unforeseen events beyond
          the prevented party's reasonable control and cannot be prevented with
          reasonable care. However, any shortage of credit, capital or finance
          shall not be regarded as an event beyond a Party's reasonable control.
          The Pledgeeffected by Force Majeure who claims for exemption from
          performing any obligations under this Agreement or under any Article
          herein shall notify the other party of such exemption promptly and
          advice him of the steps to be taken for


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          completion of the performance.

     12.2 The Pledge effected by Force Majeure shall not assume any liability
          under this Agreement. However, subject to the Pledgeeffected by Force
          Majeure having taken its reasonable and practicable efforts to perform
          this Agreement, the Party claiming for exemption of the liabilities
          may only be exempted from performing such liability as within
          limitation of the part performance delayed or prevented by Force
          Majeure. Once causes for such exemption of liabilities are rectified
          and remedied, the parties agree to resume performance of this
          Agreement with their best efforts.

13.  Dispute Resolution

     13.1 This Agreement shall be governed by and construed in accordance with
          the PRC law.

     13.2 The parties shall strive to settle any dispute arising from the
          interpretation or performance, or in connection with this Agreement
          through friendly consultation. In case no settlement can be reached
          through consultation, each party can submit such matter to China
          International Economic and Trade Arbitration Commission ("CIETAC") for
          arbitration. The arbitration shall follow the current rules of CIETAC,
          and the arbitration proceedings shall be conducted in Chinese and
          shall take place in Shanghai. The arbitration award shall be final and
          binding upon the parties.

14.  Notice

     14.1 Any notice which is given by the parties hereto for the purpose of
          performing the rights, duties and obligations hereunder shall be in
          writing. Where such notice is delivered personally, the time of notice
          is the time when such notice actually reaches the addressee; where
          such notice is transmitted by telex or facsimile, the notice time is
          the time when such notice is transmitted. If such notice does not
          reach the addressee on business date or reaches the addressee after
          the business time, the next business day following such day is the
          date of notice. The delivery place is the address first written above
          of the parties hereto or the address advised in writing including
          facsimile and telex from time to time.

15.  Appendices

     15.1 The appendices to this Agreement are entire and integral part of this
          Agreement.

16.  Effectiveness


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     16.1 This agreement and any amendments, modification, supplements,
          additions or changes hereto shall be in writing and come into effect
          upon being executed and sealed by the parties hereto.

     16.2 This Agreement is written in Chinese and is executed in two
          counterparts.


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     (No text on this page)

The Pledgee: Shanghai Huitong Information Co.,Ltd. (company seal0

Authorized Representative: [seal]


The Pledgor: Zhangrong


        [signature]        (Signature)
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EXHIBIT A

1.   Register of Shareholders of Shanghai Unlink Co., Ltd.

2.   Certificate of Capital Contribution of Shanghai Unlink Co., Ltd.

3.   Exclusive Technical Consulting and Services Agreement


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