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                                                                    Exhibit 10.4

                            ASSIGNMENT OF INVENTIONS

         THIS  ASSIGNMENT OF INVENTIONS  ("Assignment")  is entered into on this
the 4th day of  February,  2004,  with an  effective  date  of  April  15,  2003
("Effective  Date"), by and between Dwango North America Corp.  ("Assignee"),  a
Nevada  corporation  with a principal  place of business at 5847 San Felipe St.,
Suite 3220,  Houston,  Texas  77057-3000,  and  [Assignor  name],  an individual
residing [Assignor address] ("Assignor").

         WHEREAS Assignor was employed by and/or otherwise  provided services to
Over-the-Air Wireless,  Inc. ("OTA") during the period from May 2002 until April
15, 2003;

         WHEREAS  contemporaneously  herewith,  Assignor  has  entered  into  an
agreement  with  Assignee  entitled  "Agreement  and  Plan of  Merger"  ("Merger
Agreement"),  wherein, inter alia, Assignor transferred all his right, title and
interest in OTA to  Assignor,  including,  but not  limited to all  Intellectual
Property Rights held by OTA; and,

         WHEREAS  in  conjunction  with  and as a  material  part of the  Merger
Agreement,  Assignor and Assignee desire to clearly  establish that Assignee has
acquired all Assignor's right, title and interest in all Assignor's Intellectual
Property Rights arising out of or related to his employment with OTA;

         NOW,  THEREFORE,  for  and  in  consideration  of the  mutual  promises
contained herein,  the mutual promises contained in the Merger Agreement and for
other good and valuable  consideration,  the receipt and sufficiency of which is
hereby  acknowledged,  Assignee  and  Assignor  (hereinafter  collectively  "the
Parties" and each a "Party") do hereby agree as follows:

1.       DEFINITIONS

         a.       "Intellectual  Property  Rights"  shall  mean  all  copyrights
                  (including,   without  limitation,   the  exclusive  right  to
                  reproduce, distribute copies of, display and thereupon perform
                  the copyrighted  work and to prepare  derivative  works);  all
                  copyright  registrations and  applications;  all moral rights;
                  all author's rights; all trademark rights (including,  without
                  limitation,  registrations and applications); all right, title
                  and interest in and to any patent, letters patent,  industrial
                  model,  design patent,  petty patent,  patent of  importation,
                  utility model, certificate of invention,  and/or other indicia
                  of   inventorship   and/or   invention   ownership,   and  any
                  application  for any of the foregoing,  and including any such
                  rights  granted upon any reissue,  division,  continuation  or
                  continuation-in-part  applications  now  or  hereafter  filed,
                  related to any such  application;  all trade  names;  all mask
                  work rights; all right, title and interest in and to all trade
                  secret rights arising under the common law, state law, federal
                  law or the laws of any foreign  country;  all algorithms;  all
                  rights in packaging,  goodwill and other intellectual property
                  rights; and all divisions,  continuations,  reissues, renewals
                  and extensions thereof,  regardless of whether any such rights
                  arise under the laws of the United  States or any other state,
                  country or jurisdiction, and all derivative works thereof.

2.       ASSIGNMENT

         Assignor hereby  unconditionally  and irrevocably assigns and transfers
         to Assignee all of Assignor's  Intellectual Property Rights arising out
         of or  related  to any  work or  services  Assignor  performed  for OTA
         (regardless  of whether  Assignor  was  actually  compensated  for such
         services),  including  but not  limited  to all  Intellectual  Property
         Rights  arising  out of  any  research  or  development  work  Assignor
         performed either at the request of OTA or using any equipment,


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         supplies, facility or trade secret information of OTA (collectively all
         such Intellectual Property Rights "OTA IP").

         Assignor  agrees  that  all OTA IP shall be the  absolute  property  of
         Assignee or  Assignee's  designees  and,  at the  request of  Assignee,
         Assignor shall provide any reasonably  necessary assistance to Assignee
         in making  application in due form for United States letters patent and
         foreign  letters  patent  on such OTA IP. In the  event  that  Assignee
         requests  that  Assignor  provide  such  application  assistance  after
         termination of Assignor's employment with Assignee,  Assignee agrees to
         compensate  Assignor for time spent providing the requested  assistance
         at a rate equal to the most recent  hourly rate  Assignee paid Assignor
         for his services.  In calculating such hourly rate, it shall be assumed
         that  Assignor  works  forty  (40)  hours per week to earn his  salary.
         Assignor  shall  execute  any  and  all  instruments  and do  any  acts
         necessary or  desirable in  connection  with any such  application  for
         letters patent in order to establish and perfect in Assignee the entire
         right,  title,  and  interest  in such OTA IP, and also to execute  any
         instruments  desirable in connection with any continuations,  renewals,
         or reissues  thereof or in the conduct of any  related  proceedings  or
         litigation.  Assignee shall bear all reasonably necessary out of pocket
         expenses  incurred by Assignor  as a result of the  performance  of the
         obligations  provided  for in this Section 2. Except as  authorized  by
         Assignee (in writing if after termination of Assignor's employment with
         Assignee),  Assignor shall not disclose,  directly or  indirectly,  any
         information relating to any OTA IP.

         If Assignor  has any  Intellectual  Property  Rights to any OTA IP that
         cannot  be  assigned  to   Assignee,   Assignor   unconditionally   and
         irrevocably  waives the enforcement of such rights,  and all claims and
         causes of action of any kind against  Assignee with respect to such OTA
         IP, and agrees,  at Assignee's  request and expense,  to consent to and
         join in any  action  to  enforce  Assignee's  rights  in the OTA IP. If
         Assignor has any Intellectual Property Rights in any OTA IP that cannot
         be assigned to Assignee or waived by  Assignor,  the  Assignor,  to the
         extent  Assignor  has the  legal  right to do so,  unconditionally  and
         irrevocably  grants to  Assignee  during  the term of such  rights,  an
         exclusive,   irrevocable,   perpetual,   worldwide,   fully   paid  and
         royalty-free license, with rights to sublicense through multiple levels
         of sublicensees,  to reproduce, create derivative works of, distribute,
         publicly  perform and publicly  display by all means now known or later
         developed, to the OTA IP.

3.       MISCELLANEOUS

         a.       The Parties  hereby  acknowledge  and agree that breach of the
                  covenants  and  Assignments  contained in Paragraphs 2 of this
                  Assignment  shall cause  immediate and  irreparable  damage to
                  Assignee and that Assignee's remedy at law for any such breach
                  would be  inadequate.  Assignor  agrees that Assignee shall be
                  entitled to have  temporary  or  permanent  injunctive  relief
                  without the necessity of proof of actual damage or bond.  Such
                  injunctive  relief  shall  not be  exclusive,  but shall be in
                  addition to any other  rights or  remedies  to which  Assignee
                  shall be entitled.  In any dispute under this Assignment,  the
                  Parties agree that the  prevailing  Party shall be entitled to
                  recover  the costs and  expenses  of such  dispute,  including
                  reasonable attorneys' fees and costs.

         b.       The Parties agree that any failure by Assignee to exercise any
                  of its rights under this Assignment or at law, or to insist on
                  the complete  performance of all obligations by Assignor under
                  the  terms  of this  Assignment  shall  not  constitute  or be
                  construed  as a  waiver  by  Assignee  of any  of its  rights,
                  privileges, obligations or duties, or as creating any contrary
                  custom or course of conduct.


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         c.       The  Parties  agree that this  Assignment  shall be  construed
                  under  and in  accordance  with the laws of the State of Texas
                  (excluding  its conflicts of law  provisions)  and that all of
                  the  obligations  of the  Parties  are  performable  in Harris
                  County, Texas.

         d.       The Parties agree that this Assignment shall be binding on and
                  inure to the  benefit of the  Parties to this  Assignment  and
                  their  respective  heirs,  executors,   administrators,  legal
                  representatives, successors, and assigns.

         f.       The Parties agree that if any provision of this  Assignment is
                  for any reason held to be invalid, illegal or unenforceable in
                  any  respect,  the  remaining  provisions  will remain in full
                  force and effect.  If any provision of this Assignment is, for
                  any reason, determined by a court of competent jurisdiction to
                  be excessively  broad or  unreasonable as to scope or subject,
                  such provision must be enforced to the extent  necessary to be
                  reasonable  under  the   circumstances   and  consistent  with
                  applicable  law while  reflecting  as closely as possible  the
                  intent of the parties as expressed herein.

         g.       The Parties agree that,  excluding the Merger Agreement,  this
                  Assignment  supersedes any prior  understanding  or written or
                  oral  agreements   between  the  Parties  to  this  Assignment
                  concerning the subject matter hereof.

h.                This Assignment may be transmitted by facsimile, and it is the
                  intent  of the  Parties  for the  facsimile  of any  autograph
                  printed by a  receiving  facsimile  machine to be an  original
                  signature and for the facsimile and any complete  photocopy of
                  the Assignment to be deemed an original.

         i.       This  Assignment may be executed in two or more  counterparts,
                  each of which  shall be  deemed an  original  and all of which
                  together shall constitute one instrument.


                            [signature page follows]





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DWANGO NORTH AMERICA CORP.



By:
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         Robert E. Huntley, Chairman


[Assignor]



--------------------------------------------
[Assignor]






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