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                                                                     EXHIBIT 4.6



         SECOND SUPPLEMENTAL INDENTURE (this "Second Supplemental Indenture"),
dated as of February 15, 2000, by and among Source Media, Inc., a Delaware
corporation (the "Company"), the Subsidiary Guarantors, and U.S. Trust Company
of Texas, N.A., a banking corporation organized and existing under the laws of
the State of Texas, in its capacity as Trustee under the Indenture referred to
below (in such capacity, the "Trustee") and in its capacity as Escrow Agent
pursuant to the Escrow and Disbursement Agreement referred to below (in such
capacity, the "Escrow Agent") and in its capacity as Collateral Agent pursuant
to the Security Agreements referred to below (in such capacity, the "Collateral
Agent").


                                    RECITALS:


         WHEREAS, on October 30, 1997 the Company issued its 12% Senior Secured
Notes Due 2004 in the aggregate principal amount of $100,000,000 pursuant to an
Indenture, dated as of October 30, 1997, between the Company and the Trustee
(the "Original Indenture");

         WHEREAS, the Original Indenture was amended and supplemented by a First
Supplemental Indenture dated as of November 1, 1999 (the Original Indenture, as
so amended and supplemented, is herein called the "Indenture");

         WHEREAS, Section 9.02 of the Indenture provides that the Company and
the Trustee may amend or supplement the Indenture with the written consent of
the Holders of not less than a majority in aggregate principal amount of the
outstanding Securities (the "Majority Holders");

         WHEREAS, Section 9.02(b) of the Indenture provides that upon the
request of the Company and the Subsidiary Guarantors accompanied by Board
Resolutions of their respective Boards of Directors authorizing the execution of
a supplemental indenture, and upon the filing with the Trustee of evidence
satisfactory to the Trustee of the consent of the Majority Holders, and upon
receipt by the Trustee of the documents described in Section 7.02 and Section
9.06 of the Indenture, the Trustee shall join with the Company and Subsidiary
Guarantors in the execution of a supplemental indenture;

         WHEREAS, in connection with the Indenture the Company, SMI Holdings,
Inc., IT Network, Inc., Cableshare (U.S.) Limited and Interactive Channel, Inc.
entered into a Security Agreement (the "Company Security Agreement"),
Interactive Channel Technologies Inc. entered into a Security Agreement (the
"ICTI Security Agreement") and 1229501 Ontario Inc. entered into a Security
Agreement (the "1229501 Security Agreement," and collectively, with the Company
Security Agreement and the ICTI Security Agreement, the "Security Agreements"),
each dated as of October 30, 1997 in favor of the Trustee in its capacity as
collateral agent for the ratable benefit of the Holders;

         WHEREAS, in connection with the Indenture the Company entered into an
Escrow and Disbursement Agreement dated October 30, 1997 with U.S. Trust Company
of Texas, N.A. in its capacity as Trustee and as Escrow Agent;



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         WHEREAS, on January 12, 2000, the Company entered into a Merger
Agreement (the "Merger Agreement") with Liberate Technologies, a Delaware
corporation ("Liberate"), Liberate Acquisition Co., a wholly-owned subsidiary of
Liberate ("Liberate Acquisition"), SourceSuite LLC, SourceSuite Acquisition LLC,
Insight Interactive, LLC and Insight Communications Company, Inc. pursuant to
which Liberate Acquisition will merge with and into SourceSuite LLC (the
"Merger"), and the ownership interests of the Company in SourceSuite LLC will be
converted into the right to receive (a) cash in an amount equal to one-half of
SourceSuite LLC's cash and cash equivalents at the time of the Merger and (b)
(i) 886,000 shares of common stock of Liberate, or (ii) 757,072 shares of common
stock of Liberate plus $15 million in cash of Liberate;

         WHEREAS, the Company has obtained the valid and unrevoked written
consents of the Majority Holders to amend and supplement the Indenture and the
related Company Security Agreement; and

         WHEREAS, all acts and proceedings required by law and under the
Indenture to constitute this Second Supplemental Indenture a valid and binding
agreement for the uses and purposes set forth herein, in accordance with its
terms, have been done and taken, and the execution and delivery of this Second
Supplemental Indenture have been in all respects duly authorized by the Company;

         NOW, THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the
Company and the Trustee hereby agree as follows for the benefit of each other
and for the equal and ratable benefit of the Holders of the Securities:

         1. DEFINITIONS. All capitalized terms not otherwise defined herein
shall have the meanings ascribed to them in the Indenture, and the rules of
construction set forth in the Indenture shall likewise govern this Second
Supplemental Indenture.

         2. AMENDMENT OF SECTION 1.01. (a) Each of the following current terms
contained in Section 1.01 of the Indenture is amended and restated in its
entirety as follows:

            "Asset Disposition" means any sale, lease, transfer, issuance or
         other disposition (or series of related sales, leases, transfers,
         issuances or dispositions that are part of a common plan) of shares of
         Capital Stock of (or any other equity interests in) a Restricted
         Subsidiary (other than directors' qualifying shares) or of any other
         property or other assets (each referred to for the purposes of this
         definition as a "disposition") by the Company or any of its Restricted
         Subsidiaries (including any disposition by means of a merger,
         consolidation or similar transaction) other than (i) a disposition by a
         Restricted Subsidiary to the Company or by the Company or a Restricted
         Subsidiary to a Wholly-Owned Subsidiary, (ii) a disposition of
         inventory in the ordinary course of business and for which adequate
         reserves have been established in accordance with GAAP, (iii) a
         disposition of obsolete or worn out equipment that is no longer useful
         in the conduct of the business of the Company and its Restricted
         Subsidiaries and that is disposed of in each case in the ordinary
         course of business, (iv) dispositions of property for net proceeds
         which, when taken collectively with the net proceeds of any other such
         dispositions under this clause (iv) that were consummated since the
         beginning of the calendar year in which such disposition is
         consummated, do not exceed $1 million, (v) transactions permitted under
         Section 5.01, (vi) Permitted Investments pursuant to clauses (xiii),
         (xiv), (xv) and (xvi) of the definition thereof, and (vii) the sale,
         transfer, exchange or other disposition of any Liberate Shares so long
         as the proceeds are used in the business of the Company.
         Notwithstanding anything to the contrary contained above, a Restricted
         Payment made in compliance



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         with Section 4.07 shall not constitute an Asset Disposition except for
         purposes of determinations of the Consolidated Coverage Ratio.

            "NewCo" means SourceSuite LLC, a Delaware limited liability company,
         and its successors and assigns.

            "Permitted Investments" means an Investment by the Company or any of
         its Restricted Subsidiaries in (i) a Wholly-Owned Subsidiary of the
         Company (other than Interactive Channel Technologies, Inc., 997758
         Ontario, Inc., Cableshare (U.S.) Limited, Cableshare International Inc.
         and 1229501 Ontario Inc.); provided, however, (A) that the primary
         business of such Wholly-Owned Subsidiary is a Permitted Business and
         (B) in the case of Investments by the Company or any of its Restricted
         Subsidiaries in Interactive Channel, Inc., in an amount not to exceed
         the amount set forth in clause (b) of Section 4.07; (ii) another Person
         if as a result of such Investment such other Person becomes a
         Wholly-Owned Subsidiary of the Company or is merged or consolidated
         with or into, or transfers or conveys all or substantially all its
         assets to, the Company or a Wholly-Owned Subsidiary of the Company,
         provided, however, that in each case such Person's primary business is
         a Permitted Business; (iii) Temporary Cash Investments; (iv)
         receivables owing to the Company or any of its Restricted Subsidiaries,
         created or acquired in the ordinary course of business and payable or
         dischargeable in accordance with customary trade terms; (v) payroll,
         travel and similar advances to cover matters that are expected at the
         time of such advances ultimately to be treated as expenses for
         accounting purposes and that are made in the ordinary course of
         business; (vi) loans and advances to employees made in the ordinary
         course of business consistent with past practices of the Company or
         such Restricted Subsidiary in an aggregate amount outstanding at any
         one time not to exceed $250,000; (vii) loans or advances to senior
         management of the Company which loans or advances are fully secured on
         the date of such loans or advances by shares of Common Stock of the
         Company owned by such senior management in an aggregate amount
         outstanding not to exceed $750,000; (viii) stock, obligations or
         securities received in settlement of debts created in the ordinary
         course of business and owing to the Company or any of its Restricted
         Subsidiaries or in satisfaction of judgments or claims; (ix) a Person
         engaged in a Permitted Business or a loan or advance to the Company the
         proceeds of which are used solely to make an investment in a Person
         engaged in a Permitted Business or a Guarantee by the Company of
         Indebtedness of any Person in which such Investment has been made;
         provided, however, that no Permitted Investments may be made pursuant
         to this clause (ix) to the extent the amount thereof would, when taken
         together with all other Permitted Investments made pursuant to this
         clause (ix), exceed $3 million in the aggregate (plus, to the extent
         not previously reinvested, any return of capital realized on Permitted
         Investments made pursuant to this clause (ix), or any release or other
         cancellation of any Guarantee constituting such Permitted Investment);
         (x) Persons to the extent such Investment is received by the Company or
         any Restricted Subsidiary as consideration for asset dispositions
         effected in compliance with the covenant described under Section 4.10;
         (xi) prepayments and other credits to suppliers made in the ordinary
         course of business consistent with the past practices of the Company
         and its Restricted Subsidiaries; (xii) Investments in connection with
         pledges, deposits, payments or performance bonds made or given in the
         ordinary course of business in connection with or to secure statutory,
         regulatory or similar obligations, including obligations under health,
         safety or environmental obligations; (xiii) the transfer, assignment,
         conveyance or licensing of the Source I/C Assets to NewCo as
         contemplated by the Contribution Agreement; (xiv) the making of capital
         contributions by the Company to NewCo pursuant to the Operating
         Agreement in an amount not to exceed, in the aggregate, the sum of $10
         million plus the net cash proceeds of one or more Equity Offerings by
         the Company to the extent the




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         intended use of proceeds is for the making of such capital contribution
         to NewCo; (xv) the transfer, exchange or other disposition by the
         Company of its ownership interests in NewCo for the Merger
         Consideration as contemplated by the Merger Agreement and (xvi) the
         making of capital contributions by the Company to SourceSuite
         Acquisition pursuant to the SourceSuite Acquisition Operating Agreement
         in an amount not to exceed, in the aggregate, the sum of $20 million,
         as well as such contribution to SourceSuite Acquisition in respect of
         the net cash proceeds of one or more equity offerings by the Company to
         the extent the intended use of proceeds, as set forth in the offering
         documents, is for the making of such capital contribution to
         SourceSuite Acquisition.

            (b) Section 1.01 of the Indenture is amended by adding the following
         new defined terms therein in their applicable alphabetical order:

            "Liberate" means Liberate Technologies, a Delaware corporation.

            "Liberate Acquisition" means Liberate Acquisition LLC, a Delaware
         limited liability company, and its successors and assigns.

            "Liberate Shares" means the shares of common stock of Liberate to be
         received by the Company pursuant to the Merger Agreement.

            "Merger" means the merger of Liberate Acquisition into NewCo
         contemplated by the Merger Agreement.

            "Merger Agreement" means the Merger Agreement and Plan of
         Reorganization dated as of January 12, 2000 by and among Liberate,
         Liberate Acquisition, NewCo, SourceSuite Acquisition, the Company,
         Insight and Insight Communications.

            "Merger Consideration" means (a) either (i) 886,000 Liberate Shares
         or (ii) 757,072 Liberate Shares plus $15 million in cash, and (b) cash
         in an amount equal to one-half of the cash and cash equivalents of
         NewCo at the time of the Merger less any taxes payable by NewCo on the
         sale of the Retained Business to SourceSuite Acquisition.

            "Retained Business" means the Interactive Channel business of NewCo
         including its server-side interactive programming guide and related
         content business but excluding assets and properties used in its
         VirtualModem business.

            "SourceSuite Acquisition" means SourceSuite Acquisition LLC, a
         Delaware limited liability company, and its successors and assigns.

            "SourceSuite Acquisition Operating Agreement" means the limited
         liability company operating agreement of SourceSuite Acquisition, to be
         entered into by and between the Company and Insight as of the closing
         date of the Merger, as the same may be amended or modified from time to
         time in accordance with the terms thereof.

         3. AMENDMENT OF SECTION 4.11. Section 4.11 of the Indenture is amended
and restated in its entirety as follows:




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            (a) The Company will not, and will not permit any of its Restricted
         Subsidiaries to, directly or indirectly, enter into or conduct any
         transaction or series of related transactions (including the purchase,
         sale, lease or exchange of any property or the rendering of any
         service) with or for the benefit of any Affiliate of the Company, other
         than a Wholly-Owned Subsidiary (an "Affiliate Transaction") unless: (i)
         the terms of such Affiliate Transaction are no less favorable to the
         Company or such Restricted Subsidiary, as the case may be, than those
         that could be obtained at the time of such transaction in arm's length
         dealings with a Person who is not such an Affiliate; (ii) in the event
         such Affiliate Transaction involves an aggregate amount in excess of $1
         million, the terms of such transaction have been approved by a majority
         of members of the Board of Directors of the Company and by a majority
         of the disinterested members of such Board, if any (and such majority
         or majorities, as the case may be, determines that such Affiliate
         Transaction satisfies the criteria in (i) above); and (iii) in the
         event such Affiliate Transaction involves an aggregate amount in excess
         of $2 million, the Company has received a written opinion from an
         independent investment banking firm of nationally recognized standing
         that such Affiliate Transaction is fair to the Company or such
         Restricted Subsidiary, as the case may be, from a financial point of
         view; provided, however, that this clause (iii) shall not apply to (x)
         any transaction between or among the Company and its Restricted
         Subsidiaries, on the one hand, and NewCo and its Affiliates, on the
         other hand, (y) any transaction between or among the Company and its
         Restricted Subsidiaries, on the one hand, and SourceSuite Acquisition
         and its Affiliates, on the other hand and (z) the sale, exchange or
         other disposition of any Liberate Shares so long as the proceeds are
         used in the business of the Company.

            (b) The foregoing paragraph (a) shall not apply to (i) any
         Restricted Payment permitted to be made pursuant to Section 4.07, (ii)
         any issuance of securities, or other payments, awards or grants in
         cash, securities or otherwise pursuant to, or the funding of,
         employment arrangements, or any stock options and stock ownership plans
         for the benefit of employees, officers and directors, consultants and
         advisors approved by the Board of Directors of the Company, (iii) loans
         or advances to employees in the ordinary course of business of the
         Company or any of its Restricted Subsidiaries in aggregate amount
         outstanding not to exceed $250,000 at any time, (iv) loans or advances
         to senior management of the Company which loans and advances are fully
         secured on the date of such loans or advances by shares of Common Stock
         of the Company owned by such senior management, in an aggregate amount
         outstanding not to exceed $750,000, (v) indemnification agreements
         with, and the payment of fees and indemnities to, directors, officers
         and employees of the Company and its Restricted Subsidiaries, in each
         case in the ordinary course of business, (vi) transactions pursuant to
         agreements in existence on the Issue Date which are (x) described in
         the Offering Memorandum or (y) otherwise, in the aggregate, immaterial
         to the Company and its Restricted Subsidiaries taken as a whole, (vii)
         any employment, non-competition or confidentiality agreements entered
         into by the Company or any of its Restricted Subsidiaries with its
         employees in the ordinary course of business, (viii) the issuance of
         Capital Stock of the Company (other than Disqualified Stock), (ix)
         Permitted Investments pursuant to clauses (xiii), (xiv), (xv) and (xvi)
         of the definition thereof and (x) any transaction or arrangement
         entered into pursuant to the Contribution Agreement or the Purchase
         Agreement.




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         4. RELEASE OF COLLATERAL. In accordance with the preceding amendments
to be made to the Indenture , concurrently with the effectiveness of the Merger,
the Trustee releases any and all liens upon and security interests in the
Collateral (as defined in the Company Security Agreement) to the extent such
Collateral consists of Membership Units of NewCo. Upon the request of the
Company, and at the Company's expense, the Trustee will execute and deliver such
lien releases and/or termination statements and documents as may be necessary to
effectively terminate any and all of such liens and/or security interests on any
public record.

         5. ADDITIONAL COLLATERAL. In addition to the Collateral set forth in
the Company Security Agreement, concurrently with the effectiveness of the
Merger, the Company grants to the Trustee, in its capacity as Collateral Agent
under the Company Security Agreement and subject to the terms and conditions of
the Company Security Agreement, a security interest for the benefit of the
Holders (as defined in the Company Security Agreement) in the Company's right,
title and interest in the ownership interests of SourceSuite Acquisition and in
the Liberate Shares.

         6. EFFECTIVENESS. This Second Supplemental Indenture will become a
valid and binding obligation of the parties hereto upon execution but the
amendments and supplements to the Indenture effected hereby shall become
operative and effective only concurrently with the effectiveness of the Merger.
If the Merger is not effected by April 15, 2000 or such later date as is agreed
to by the parties to the Merger Agreement, this Second Supplemental Indenture
shall be null and void. Concurrently with such effectiveness, all references to
the Indenture shall, unless specifically referring to the Indenture as
originally executed, be deemed to be references to the Indenture as amended and
supplemented by this Second Supplemental Indenture. The Indenture, the Security
Agreements and the Escrow Agreement, as amended and supplemented by this Second
Supplemental Indenture, are in all respects hereby ratified and confirmed.

         7. RECITALS. The recitals contained herein shall be taken as the
statement of the Company, and the Trustee assumes no responsibility for the
correctness of the same. The Trustee makes no representation as to the validity
of this Second Supplemental Indenture.

         8. SUCCESSORS AND ASSIGNS. This Second Supplemental Indenture shall be
binding upon and inure to the benefit of the parties hereto and their respective
successors and assigns. Except as amended herein, the terms, provisions and
covenants of the Indenture shall remain in full force and effect and continue to
govern the parties thereto.

         9. COUNTERPARTS. This Second Supplemental Indenture may be executed in
any number of counterparts, each of which so executed shall be an original, but
all of them together represent the same agreement.

         10. GOVERNING LAW. This Second Supplemental Indenture shall be governed
by, and construed in accordance with, the laws of the State of New York, but
without giving effect to applicable principles of conflicts of law to the extent
that the application of the laws of another jurisdiction would be required
thereby.

                        [Remainder of page intentionally
                         left blank; signatures follow]




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         IN WITNESS WHEREOF, the parties have caused this Second Supplemental
Indenture to be duly executed, all as of the date first above written.


                                      COMPANY:


                                      SOURCE MEDIA, INC.


                                      By: /s/ Stephen W. Palley
                                         --------------------------------------
                                         Stephen W. Palley
                                         Chief Executive Officer and President


                                      SUBSIDIARY GUARANTORS:


                                      SMI HOLDINGS, INC.


                                      By: /s/ Stephen W. Palley
                                         --------------------------------------
                                         Stephen W. Palley
                                         Chief Executive Officer and President


                                      IT NETWORK, INC.


                                      By: /s/ Stephen W. Palley
                                         --------------------------------------
                                         Stephen W. Palley
                                         Chief Executive Officer


                                      INTERACTIVE CHANNEL, INC.


                                      By: /s/ Stephen W. Palley
                                         --------------------------------------
                                         Stephen W. Palley
                                         Chief Executive Officer

                                      INTERACTIVE CHANNEL TECHNOLOGIES INC.

                                      By: /s/ Stephen W. Palley
                                         --------------------------------------
                                         Stephen W. Palley
                                         Chief Executive Officer




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                                      1229501 ONTARIO, INC.


                                      By: /s/ Stephen W. Palley
                                         ------------------------------------
                                         Stephen W. Palley
                                         Chief Executive Officer and President


                                      997758 ONTARIO, INC.


                                      By: /s/ Stephen W. Palley
                                         ------------------------------------
                                         Stephen W. Palley
                                         Chief Executive Officer and President


                                      CABLESHARE (U.S.) LIMITED


                                      By: /s/ Stephen W. Palley
                                         ------------------------------------
                                         Stephen W. Palley
                                         Chief Executive Officer and President


                                      CABLE SHARE INTERNATIONAL INC.


                                      By: /s/ Stephen W. Palley
                                         ------------------------------------
                                         Stephen W. Palley
                                         Chief Executive Officer and President


                                      CABLESHARE B.V.


                                      By: /s/ Brad Unsworth
                                         ------------------------------------
                                         Brad Unsworth
                                         Managing Director



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                                      TRUSTEE:


                                      U.S. TRUST COMPANY OF TEXAS, N.A.,
                                      AS TRUSTEE


                                      By: /s/ Bill Barber
                                         ------------------------------------
                                         Name: Bill Barber
                                         Title: Vice President


                                      COLLATERAL AGENT:


                                      U.S. TRUST COMPANY OF TEXAS, N.A.,
                                      AS COLLATERAL AGENT


                                      By: /s/ Bill Barber
                                         ------------------------------------
                                         Name: Bill Barber
                                         Title: Vice President


                                      ESCROW AGENT:


                                      U.S. TRUST COMPANY OF TEXAS, N.A.,
                                      AS ESCROW AGENT


                                      By: /s/ Bill Barber
                                         ------------------------------------
                                         Name: Bill Barber
                                         Title: Vice President




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