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                                                                   EXHIBIT 10.21

                         BUSINESS COOPERATION AGREEMENT
                                       ON
                       MONTERNET SHORT-MESSAGING SERVICES

                                                        Agreement code:
                                                        Execution date:


PARTY A:   BEIJING MOBILE TELECOMMUNICATIONS CO., LTD
Legal representative:    Yuejia Sha
Mail address:            No. 58, Dong Zhong Street, Dongcheng District, Beijing,
                         100027, China
Tel:                     65546699
Fax:                     65541330
Opening bank:
Bank account:


PARTY B: BEIJING AIRINBOX INFORMATION TECHNOLOGIES CO., LTD
Legal representative:    Yunfan Zhou
Mail address:            Yuetan Tower A-809, No. 2, North Yuetan Street, Xicheng
                         District, Beijing, 100047, China
Tel:                     68081818
Fax:                     68083118
Opening bank:            Xinjiekou Branch, Dewai office of ICBC
Bank account:            0200001309006796982

      BEIJING MOBILE TELECOMMUNICATIONS CO., LTD (hereinafter referred to as
"Party A"), as the mobile communication operator and mobile data service
operator, provides open and premium-based communication channels for the
application providers. BEIJING AIRINBOX INFORMATION TECHNOLOGIES CO., LTD
(hereinafter referred to as "Party B"), as a company engaged in the value-added
communication services approved by the competent telecom authorities, provides
value-added short-message services to MP users of China Mobile. To provide
better application services to users,

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the parties agree as follows as to the joint development of Monternet
short-message services upon adequate consultation in the principle of equality,
mutual benefit and concerted growth.


ARTICLE 1     BASIC DESCRIPTION OF COOPERATION

1.   Party B shall be fully compliant with the requirement of Internet
     Content/Application Service Management Methods of the State Council Order
     (No.292), be granted with License for the Value-added Telecommunications
     Services (business scope defined as Wireless Network Value-added
     Telecommunications Services) and License for Telecommunications and
     Information Services (business scope defined as Internet Information
     Services), be able to provide comprehensive after service system, and
     have legal and reliable information/message sources and other legal
     business operation conditions.

2.   In case Party B is the local partner of Party A, Party B shall provide
     Monternet short-message services only to China Mobile MP users in Beijing
     region via the short-message channels of Party A.

3.   Party B shall conduct its short-message value-added services in compliance
     with the Monternet SP Cooperation Regulations (including but not limited to
     the Short-Message Value-added Services SP Cooperation Administration
     Guideline promulgated by Beijing Mobile and China Mobile Telecommunications
     Group Corp.).

4.   Party A shall conduct regular evaluation of Party B based on the Monternet
     SP Cooperation Regulations, and is entitled to terminate the cooperation
     with Party B in case that Party B fails to pass such examination.


ARTICLE 2     RIGHTS AND OBLIGATIONS

1.   Party A's rights and obligations

1.1  Party A allows Party B to provide short-message value-added services to
     users via the short-message gateway of Party A. Party A is entitled to
     adjust the short-message traffic volume according to the capacity of the
     short-message center. If such adjustment shall impact on the business of
     Party B, Party A shall promptly notify Party B thereof.

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1.2  Party A shall provide comprehensive GSM mobile communication system, and
     ensure smooth and stable information transmission. Upon the notification of
     Party B of any communication failure, Party A shall promptly settle the
     failure to avoid impairment of Party B's business.

1.3  Party A shall make available the technical protocol, standard and interface
     standard relevant to the short-message gateway platform to Party B. Party A
     shall provide the technical documentation for mutual communication, and
     promptly address communication problems of Party B.

1.4  Party A shall supply the hardware/software system for the short-message
     platform, and bear the relevant operation cost.

1.5  Party A shall renovate its own billing system, including the
     commission-based collection system of the banks, and bear the cost of
     necessary hardware and software.

1.6  Party A shall undertake the billing and payment collection on behalf of
     Party B. Party A is entitled to check the business of Party B to ensure the
     accurate billing data. Party A shall issue explicit information premium
     invoice to users and the information premium bill at the request of the
     user.

1.7  When applicable, Party A shall provide the relevant data of Monternet
     invalid users (number canceling, service discontinuance and overdue
     information premium) to Party B to facilitate Party B to dispose of such
     invalid Monternet users promptly.

1.8  Party A shall be responsible for the handling of customer enquiries and
     complaints resulted from telecommunications network failures.


2.   Party B's rights and obligations

2.1  Party B shall undertake the building and maintenance of its own software
     and hardware, including but not limited to all hardware, system
     commissioning, cutover, system maintenance, routine business management and
     marketing efforts/cost of the subject project.

2.2  Party B shall provide the agreed contents and application services to China
     Mobile users. Party B shall ensure the legal, prompt and reliable
     information sources. Party B shall guarantee that its information and
     content are compliant with applicable policies, laws and regulations, and
     be liable for any consequence arising out of illegal contents.

2.3  Party B's Website with customization interface for users is:

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     http://www.kongzhong.com, inform users of the contents and service provided
     by Party B. The customization interface of Party B shall provide basic
     service functions like authentication, adding, deleting, modifying and
     searching, and allow users to inquire about the information premium list.
     Party B shall provide explicit premium standards to users with the premium
     standard changing frequency not less than 6 months. That is to say, the
     premium standard of a service (new service or changed service) shall not be
     changed within the first 6 months. Party B shall keep complete use records
     of all users of at least 3 months, keep the user ordering data permanently,
     and provide the interface to Party A to inquire about the service records.

2.4  Party B shall take necessary measures to effectively control invalid
     Monternet users. To ensure normal operation of Monternet business, Party B
     shall not send any information to invalid Monternet users it get to know.

2.5  In case the system failure of Party B impairs the communication system of
     Party A, Party B shall submit to the adjustment arrangement of Party A to
     the short-message traffic volume to ensure normal and stable short-message
     service, and settle any user complaint thus incurred at its own cost.

2.6  Party B shall not send ads and other irrelevant information to users via
     the communication channels of Party A during the term of this agreement.
     Party B shall strengthen the check of the short-message contents, restrict
     the group-calling numbers (at most 2 each time) and sending times in each
     time unit (not over 100 each hour). Party B shall take technical measures
     against illegal attack, unauthorized use of passwords, unauthorized
     convoking of web pages and other illegal acts impairing Monternet business
     information security.

2.7  Party B shall be responsible for the handling of customer enquiries as to
     bills, of customer enquiries and complaints with regards to the contents
     and/or application services provided by Party B, and such handling should
     be finished within a stated time frame with a fair and honest solution.

2.8  During the term of this Agreement, Party B is obligated to furnish the
     monthly report within the first 5 days each month as requested by Party A
     to Party A, stating the user development, user categories, user habits,
     business forecast and others, the monthly report format as set out in
     Exhibit 1 hereto. Party A shall keep the confidentiality of such data
     according to Article 8 hereto.

2.9  Party B is obligated to market and promote Monternet services.

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ARTICLE 3     DISTRIBUTION OF RIGHTS AND OBLIGATIONS

1    Party B shall address the user disputes arising out of contents, services
     or transmission failure between the parties. Party A shall address the user
     disputes arising out of the short-message gateway and center, with the
     maintenance labor-division as follows: (Graph omitted)

2    The contents or applications provided by Party B shall be within the
     business scope mutually agreed, otherwise Party A is entitled to terminate
     this Agreement with Party B liable to the default penalty. Party A is
     entitled to supervise the business development of Party B, Party B shall
     assist the efforts of Party A in this regard in an effort to avoid negative
     impact on normal business of Party A by the business of Party B. In case
     the business development of Party B negatively impairs the normal business
     of Party A due to the violation against this Agreement, Party A is entitled
     to terminate this Agreement with Party B liable for the default liability.

3    Party B shall apply to Party A in writing or through SP Management Website,
     with the official request chopped with company seal prior to adding or
     withdrawing any services hereunder or changing the price of some services.
     In case of approving the change of certain service prices, Party A shall
     notify Party B of such approval in writing or through SP Management
     Website. In case of Party A's written consent of adding certain services by
     Party B, Party B shall test the added services and submit to Party A test
     reports. Party B shall not provide such new services to users prior to
     Party A's acceptance of the sophistication of such services. Details refer
     to Exhibit 1 hereto.


ARTICLE 4     REVENUES OF THE PARTIES

1    Party A shall charge mobile phones users communication premium generated
     while using short-message services according to information charges
     standard. In principle, Party B shall determine the information service
     premium for the services hereunder used by the MP users subject to the
     approval of China Mobile Corporation. Party A suggests the upper threshold
     of the information service premium (maximum RMB 2 yuan/message, RMB 30
     yuan/month for monthly services). Party B shall submit the premium
     standards to the price administration

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     authorities, and promptly notify Party A accordingly.

2    Party A shall provide the billing service and premium collection service to
     Party B. All information service premium of Beijing region users of each
     billing month shall be the due information service premium in Beijing.
     Party A shall pay 85% of the due information service premium of Beijing to
     Party B, and be liable to the risk of overdue payment of local users. In
     case Party B is the full-network partner of Party A, i.e. Party B provide
     Monternet short-message value-added services to nationwide China Mobile
     users in China, then all information service premium of non-Beijing users
     recorded in each billing month shall be the due information service premium
     of non-Beijing regions, which shall be collected by local subsidiaries of
     China Mobile. Relevant local subsidiaries of China Mobile will credit 85%
     local due information service premium to Party A, which shall then be
     transferred to Party B by Party A in full.

3    In case the monthly short-message entries (downlink) sent by Party B to
     nationwide users as recorded in the gateway billing data exceeds those sent
     by users to Party B (uplink), thus resulting in ill-balanced communication
     premium of Party B (the balance of downlink messages and uplink messages is
     the ill-balance communication), Party A shall charge RMB 0.05-0.10
     yuan/message for the ill-balance communication as follows:

<TABLE>
<CAPTION>
-------------------------------------------------------------------------------------------------------
Ill-balanced downlink
SM traffic                Premium standard    Calculation methods
(messages/month)          (RMB yuan/message)  X=(MT-MO) message/month
-------------------------------------------------------------------------------------------------------
<S>                       <C>                 <C>
Below 100,000             0.08                X*0.08, at least RMB 2000 yuan
-------------------------------------------------------------------------------------------------------
100,000-300,000           0.07                (X-100,000)*0.07+100,000*0.08
-------------------------------------------------------------------------------------------------------
300,000-1 million         0.06                (X-300,000)*0.06+200,000*0.07+100,000*0.08
-------------------------------------------------------------------------------------------------------
Over 1 million            0.05                (X-1.million)*0.05+700,000*0.06+200,000*0.07+100,000*0.08
-------------------------------------------------------------------------------------------------------
</TABLE>


ARTICLE 5     SETTLEMENT MODEL

1    Settlement point: determined by Party A.

2    Settlement methods

2.1  Party B shall link with the short-message center of Party A via the
     short-message

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     gateway of Party A, which shall record the billing data as final. The
     monthly settlement from the 15th day to the 20th day each month shall cover
     the premium of the last month from the 1st day to the last day. After the
     normal billing accounting period, Party A shall calculate the current-month
     information service premium of Party B and the ill-balance communication
     premium payable to Party A, which shall serve as the basis of settlement
     between the parties.

2.2  The parties shall make the account settlement of the current-month
     information service premium according to the records of the billing system
     of Party A, Party A shall pay the balance of 85% information service
     premium minus the ill-balance communication against the formal service
     invoices. In case the balance is above zero, Party A shall pay the balance
     to Party B. In case the balance is below zero, Party B shall pay the
     balance to Party A against the invoices furnished by Party A. The payment
     collecting party shall mail the invoice within three (3) days after the
     receipt of the payment (by local post stamp).

2.3  The parties shall make the settlement and payment strictly according to the
     regulations of settlement model and schedule. In case either party delays
     the due payment beyond the stipulated time (the 20th day each month), the
     party shall pay to the other party the delay penalty at the daily rate of
     1% of the delayed payment. In case either party fails to make payment
     overdue for over 2 months after the notice of the other party, the
     conforming party is entitled to lodge an action against the default party
     with the legal liability borne by the default party.


ARTICLE 6     MARKETING AND PROMOTION

1    The parties shall engage in joint marketing and promotion with their
     respective resources in the principle of mutual benefit.

2    Party A in general shall market/promote Monternet and the major categories
     of application services instead of the cooperative Monternet services
     separately.

3    Party B shall market/promote its brand and relevant Monternet services as
     well as the brand of Monternet. Party B shall strictly abide by the
     brand/marks regulations of Party A in use of Monternet LOGO without
     unauthorized distortion or color change with prior approval of Party A
     prior to any use thereof.

4    Party B shall not use Monternet brand for any purpose other than the
     marketing/promotion of Monternet services, otherwise Party A is entitled to
     require Party B to stop the use thereof and bear any liability thus
     incurred, or even claim the legal liability for severe violations.

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5    Party B must obviously mark the customer service phone or customer service
     Website, compliant email on any promotional material and media ads. of
     Monternet business. Party B shall not adopt the similar products of China
     Mobile rivals as the promotional gifts of Monternet business.


ARTICLE 7     CUSTOMER SERVICES

1    The Monternet short messages received by users must be those upon their
     request or customization. Party B shall ensure the wholesomeness and
     legality of the short messages sent to users, Party A is entitled to
     supervise the short message contents of Party B, and strengthen the
     management thereof, specific regulations as provided for in Exhibit 2.

2    Party B shall fully inform users of the basic elements of Monternet
     services prior to any ordering, including price, sending frequency/times,
     use model, major contents and etc.

3    Party A's customer service center 1860 and the major outlets will handle
     the customer inquiries and complaints about Monternet services, and
     transfer any customer problem about information content and services to the
     customer service center of Party B.

4    Party B shall maintain 7x24 hotlines, both a direct-dialing fixed line and
     a mobile one, while the fixed line can't be an extension line and the
     mobile phone can't be switched off or to be diverted. Numbers of such
     hotlines should be given to customers through Web pages or marketing
     materials.

5    Party B shall assign regular staff to handle user complaints, and respond
     to customer complaint within one (1) day thereafter.

6    To ensure the users' understanding of Party B's services, Party B must
     process the service recommendations, customer service instructions and the
     downlink information of user passwords free of charge, and send the service
     prompt information (e.g. price, customization confirmation, customer
     service hotline, subscription cancellation and etc.) free of information
     service premium.

7    The subscription for customized short-message services shall take effect 72
     hours after the submission of the subscription. Charges for services within
     72 hours could be done on per message basis, no monthly-payment service
     fees should be charged unless customers re-subscribe for monthly-payment
     short-message services.

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8    For monthly-payment short-message services, Party B may charge the monthly
     premium at the user for the use of the service between half a month to a
     month, and charge no premium at the user for the use of the service below
     half a month.

9    For users in request of customized services via Internet, Party B shall
     obviously mark the basic business information on the Web page prior to the
     user confirmation of the customization. After successful customization,
     Party B shall send the prompt information to users, stating "thanks to
     you", "successful confirmation of the customization", "service information
     premium standard", "sending frequency/times", "order withdrawal method",
     "customer service phone/Website".

10   For users of customized services via mobile phones, Party B shall return
     the prompt information via short message to the users (including premium
     users and third-party users) immediately, stating "thanks to you",
     "successful confirmation of the customization", "service information
     premium standard", "sending frequency/times", "order withdrawal method",
     "customer service phone", "Website" (optional).

11   To the initial ordering intentions acquired in the non-online marketing
     (e.g. filling out forms), Party B shall send the second confirmation
     message (basic service information), and confirm the actual order after
     user confirmation of the password.


ARTICLE 8     TERMINATION OF CORPORATION

     1.   Party B shall not send any information to invalid Monternet users. In
          case Party B knowingly send information to invalid Monternet users,
          Party A is entitled to require Party B to indemnify the economic loss
          incurred from user overdue payment, and is entitled to terminate this
          Agreement and the cooperation hereunder.

     2.   Party B is obligated to ensure the compliance of its information
          content with Telecom Regulations of PRC, Internet Information Service
          Regulations and other applicable laws, regulations and policies, not
          distribute any illegal and obscene information undermining the
          national security and interest, Party B shall ensure that its
          information content shall not impair the corporate image of China
          Mobile. Without written consent of Party A, Party B shall not send ads
          and other irrelevant information to mobile users via the short-message

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          ports furnished by Party A. Otherwise, Party B shall indemnify Party A
          for any loss thus incurred, and Party A is entitled to terminate this
          Agreement and the cooperation hereunder.

     3.   Upon the receipt of user complaint for receiving any un-requested
          message from Party B, Party A shall notify Party B accordingly, and
          Party B shall investigate the reasons. In this case, Party A shall not
          charge user any premium, and return any premium collected back to the
          users, and Party A is entitled to terminate this Agreement and the
          cooperation hereunder according to the current-month severity of
          customer complaints.

     4.   In case Party A transfers customer complaints to Party B, Party B
          shall respond to the customer service department of Party A within two
          (2) hours with an initial reply, and investigate the reasons/handle
          the complaint within one (1) working day. For legitimate complaints
          caused by Party B, Party A is entitled to deduct RMB 500 yuan per each
          customer complaint from the current-month due payment to Party B as
          the default compensation; for complaints submitted to the relevant
          authorities or media, Party A is entitled to deduct no less than RMB
          10,000 yuan per each customer complaint as the default compensation.
          And, Party A is entitled to terminate this Agreement and the
          cooperation hereunder according to the default severity.

     5.   Party B shall ensure that a 100% response rate as to monthly customer
          complaints (complaints handled by Party B and transferred back to
          Party A/total complaints transferred to Party B by Party A = 100%)
          shall be achieved, that complaints caused by SP are less than the
          standard number of complaints ( which equals to Beijing Mobile's
          monthly number of users of Monternet short-message services x 1.5
          /10000 x Party B's monthly number of users of Monternet short-message
          services/Monthly accumulated number of users of Monternet
          short-message services of SPs accessed through Beijing Mobile), that
          customer satisfaction (number of complaints settled with customers'
          satisfaction/total number of complaints transferred to Party B by
          Party A) is over 80%. Party A shall conduct monthly evaluation as to
          Party B's handling of complaints. In case Party B fails in such
          evaluations, Party A is entitled to deduct default compensation from
          the due payment to Party B according to the default severity; if Party
          B fails such evaluations for three (3) consecutive months, then Party
          A is entitled to terminate this Agreement and the cooperation.


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     6.   To ensure the normal marketing of Monternet services, Party B shall
          not directly or indirectly provide cross-operator short-message
          services, including domestic cross-operator short-message services and
          international short-message services, and shall not carry out
          commission-based premium collection services (referring to using
          Monternet short-message network to collect premiums that are not
          generated or realized through such network) via the short-message
          system of Party A. Otherwise, Party B shall indemnify Party A for any
          loss thus incurred, and Party A is entitled to terminate this
          Agreement and the cooperation hereunder.

     7.   In the event Party B fails to pay Party A the due payment for three
          consecutive months and fails to pay off the unpaid balance and default
          compensation, with 15 days of the delivery of past due notice, Party A
          shall have the right to close the short message gateway, and terminate
          this Agreement and the cooperation hereunder.

     8.   In the event that Party B fails to correct any breach of this
          Agreement or any violation of relevant measures (including but not
          limited to Short-Message Value- Added Services SP Cooperation
          Administration Guideline promulgated by Party A and China Mobile
          Telecommunications Group Corp.), after warning or request by Party A,
          Party A shall have the right to close the short message gateway, and
          terminate this Agreement and the cooperation hereunder.

     9.   In the event that this Agreement is terminated pursuant to any of the
          above provisions, Party B shall be responsible for all damages
          sustained by any third party.


ARTICLE 9     CONFIDENTIALITY

1    Proprietary Information refers to any valuable information developed,
     created, found or disclosed to the receiving party by the disclosing party.
     Proprietary Information includes but not limited to the trade secrets,
     intellectual property rights (IPR) and technical secrets.

2    The parties shall protect the IPR and other Proprietary Information among
     other trade secrets of its own and the other party. Without written consent
     of the other party, either party shall keep the confidentiality of the
     Proprietary Information of the other party, and shall not disclose any
     Proprietary Information involving with

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     the trade secrets and technical secrets of the other party to any third
     party.

3    The parties shall keep the confidentiality of this cooperation and this
     Agreement. Without prior written consent of the other party, either party
     shall disclose the details of the cooperation and this Agreement to any
     third party.


ARTICLE 10    DEFAULT LIABILITY

Failure of either party to perform any provision hereunder shall be deemed as
default. Upon receipt of the other party's written notice of the default, the
default party, if confirming the default, shall correct the default within
twenty (20) days thereafter with written notice to the other party. It the
notified party denies the default, it shall inform the other party thereof
within twenty (20) days or sate the reasons therefor. In this case, the parties
shall settle the dispute via consultation, or resort to the dispute settlement
provisions hereunder for any dispute failing friendly consultation, the default
party shall be liable for the loss thus incurred to the conforming party.


ARTICLE 11    LIABILITY LIMITATION

In case both party or either party fails to perform, partly or as a whole, the
obligations hereunder due to force majeure event, neither party shall be held
liable for the default liability. However, the affected party or the parties
shall notify the other party within fifteen (15) days thereafter and furnish
relevant supporting evidence. Either party or both parties shall resume the
performance of this Agreement after the elimination of the force majeure.


ARTICLE 12    DISPUTE SETTLEMENT

The parties may settle the dispute arising out of the performance hereunder via
friendly consultation. Either party may submit the dispute failing friendly
consultation to Beijing Arbitration Committee for arbitration according to its
rules. The arbitration award is final and binding upon the parties.


ARTICLE 13    EFFECTIVENESS, MODIFICATION, TERMINATION AND RENEWAL OF AGREEMENT

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1    This Agreement shall become effective on May 1, 2004 and expire on October
     31, 2004; provided however, this Agreement shall not become effective prior
     to procurement by Party B of qualifications contemplated in section 1 of
     Article 1 of this Agreement. In case the parties do not terminate this
     Agreement upon the expiration, this Agreement shall automatically renew for
     another 6 months. The party rejecting the renewal shall notify the other
     party thirty (30) days in advance of the expiration in writing or through
     email thereabout.

2    This Agreement, 14 pages, is made in four (4) copies with each party
     holding two (2) copies of equal validity. It shall take effect upon
     execution and stamp of the duly authorized representatives of the parties.

3    The exhibits hereto constitute an integral part of this Agreement with
     equal legal validity.

4    During the term of this Agreement, the parties may modify the provision
     hereunder or terminate this Agreement upon friendly consultation. Either
     party intending to change or modify this Agreement shall notify the other
     party in writing thirty (30) days in advance. The party unilaterally
     terminating this Agreement shall indemnify all loss thus incurred to the
     other party.



Party A (seal):  /s/ Xu Suming

Beijing Mobile Telecommunications Co., Ltd.

Party B (seal):  /s/ Li Luyi

Beijing AirInBox Information Technologies Co., Ltd.