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                                                                    EXHIBIT 10.4


                        STOCK PURCKASE/EXCHANGE AGREEMENT

         This Stock Purchase/Exchange Agreement (the "Agreement") is entered
into by and among Dr. Michael Hoenig and Magarete Jung ("Sellers"), individuals
residing in Germany, and CABEC ENERGY CORP. ("Purchaser"), a publicly held and
traded Delaware (U.S.A.) corporation.

                                R E C I T A L S :

         A.       Sellers own beneficially and of record in excess of 80 shares
(40%) of the 200 authorized and issued (and outstanding) shares of the Common
Stock of VIMONTA AG, a Swiss corporation (the Vimonta Stock"); and

         B.       Purchaser is authorized to issue 200,000,000 shares of Common
Stock, and Purchaser currently has approximately 133,000,000 shares of Common
Stock issued and outstanding; and

         C.       Purchaser desires to purchase from Seller, and Seller desires
to sell to Purchaser, the Vimonta Stock, in exchange for 30,000,000 shares (the
"Cabec Stock") of newly issued Common Stock of Purchaser (restricted under Rule
144, as promulgated by the United States Securities and Exchange Commission
pursuant to the Securities Act of 1933, as amended from time to time).

                                    AGREEMENT

         NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged and confessed, Sellers and Purchaser agree as follows:

1.       TRANSFER/EXCHANGE OF SHARES.

         a.       At the Closing, as such term is hereinafter defined, Sellers
agree to deliver to Purchaser the Vimonta Stock.

         b.       At the Closing, as such term is hereinafter defined, Purchaser
agrees to deliver to Sellers the Cabec Stock.

         2.       CLOSING. The closing ("Closing") shall be held on or before
March 18, 1998, or at such later time as shall be mutually acceptable to the
parties.

         3.       WARRANTIES AND REPRESENTATIONS OF SELLERS. Sellers warrant and
represent to Purchaser that Sellers (i) own the Vimonta Stock free and clear of
any claim whatsoever by any parties, (ii) Sellers have not pledged or encumbered
the Vimonta Stock in any manner, (iii) the Vimonta Stock is nonassessable, (iv)
Sellers have granted no right, warrant, purchase option, or any other right
which directly or indirectly affects the Vimonta Stock, (v) the Vimonta Stock
has voting and other rights that are identical to all other shares of VIMONTA
AG, and (vi) the Vimonta Stock is freely assignable by Sellers to Purchaser in
accordance with this Agreement.

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         4.       WARRANTIES AND REPRESENTATIONS OF PURCHASER. Purchaser
warrants and represents to Sellers that the Cabec Stock (i) is free and clear of
any claim whatsoever by any parties, (ii) is nonassessable, (iii) may be issued
to Sellers by Purchaser in accordance with this Agreement, and (iv) is
restricted pursuant to Rule 144.

         5.       AMENDMENT. This Agreement may only be altered, modified, or
amended by a written agreement signed by Sellers and Purchaser.

         6.       ENTIRE AGREEMENT. This Agreement contains the only agreement
of Sellers and Purchaser with respect to the purchase/exchange of the Vimonta
Stock and the Cabec Stock and supersedes all prior written or oral agreements,
negotiations, understandings, or commitments.

         7.       PARTIES BOUND. This Agreement shall be binding upon and inure
to the benefit of and be enforceable by Sellers and Purchaser, their heirs,
executors, administrators, successors, and assigns.

         8.       ASSIGNMENT RIGHTS. Sellers and Purchaser, in their sole
discretion, may assign their rights under this Agreement to any person or
persons.

         9.       CHOICE OF LAW; VENUE. This Agreement shall be governed by and
construed in accordance with the laws of the State of Texas (U.S.A.). VENUE FOR
ANY CAUSE OF ACTION RELATING TO THIS AGREEMENT SHALL BE EXCLUSIVELY DALLAS,
TEXAS.

         10.      FURTHER AGREEMENTS. Sellers and Purchaser agree to execute
such other and further agreements as are necessary or desirable to effect the
intent of this Agreement.

         EXECUTED to be effective as of March 11, 1998.

                                      SELLERS:


                                      -----------------------------------------
                                            DR. MICHAEL HOENIG


                                      -----------------------------------------
                                            MAGARETE JUNG


                                      PURCHASER:

                                      CABEC ENERGY CORP., a Delaware corporation


                                      By:
                                            ------------------------------------
                                            Michael John, President

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