SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
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                                   FORM 10-K/A

                                 AMENDMENT NO. 1

                                  ANNUAL REPORT

                       Pursuant to Section 13 or 15(d) of
                       The Securities Exchange Act of 1934
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      For the fiscal year ended:                 Commission file number:
        December 31, 2003                                001-16835

                          MERRILL LYNCH DEPOSITOR, INC.
                 (ON BEHALF OF PREFERREDPLUS TRUST SERIES ALL-1)
             (Exact name of registrant as specified in its charter)

               Delaware                                 13-3891329
            (State or other                         (I. R. S. Employer
            jurisdiction of                         Identification No.)
            incorporation)




       World Financial Center,                            10080
         New York, New York                            (Zip Code)
        (Address of principal
         executive offices)

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     Registrant's telephone number, including area code: (212) 449-1000

Securities registered pursuant to Section 12(b) of the Act:

PreferredPLUS Trust Certificates Series ALL-1, listed on The New York Stock
Exchange.

Securities registered pursuant to Section 12(g) of the Act:

Not Applicable.

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or

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for such shorter period that the Registrant was required to file such reports),
and (2) has been subject to such filing requirements for the past 90 days.

                              Yes [X]       No [ ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this form 10-K or any amendment to this
form 10-K.



Indicate by check mark whether the registrant is an accelerated filer (as
defined in Rule 12b-2 of the Act).

                              Yes [ ]       No [X]

State the aggregate market value of the voting and non-voting common equity held
by non-affiliates of the registrant. The aggregate market value shall be
computed by reference to the price at which the common equity was sold, or the
average bid and asked prices of such common equity, as of the last business day
of the registrant's most recently completed second fiscal quarter.

Not Applicable.

Indicate the number of shares outstanding for each of the registrant's class of
common stock, as of the latest practicable date.

Not Applicable.



                       DOCUMENTS INCORPORATED BY REFERENCE

None.

                                EXPLANATORY NOTE

Merrill Lynch Depositor, Inc. (on behalf of PreferredPLUS Trust Series ALL-1)
hereby amends its Annual Report for the fiscal year ended December 31, 2003 in
its entirety as set forth below.

     PART I

     Item 1.   Business


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               For information with respect to the underlying securities held by
               PreferredPLUS Trust Series ALL-1, please refer to Allmerica
               Financial Corporation's (Commission file number 001-13754)
               periodic reports, including annual reports on Form 10-K,
               quarterly reports on Form 10-Q and current reports on Form 8-K,
               and other information on file with the Securities and Exchange
               Commission (the "SEC"). You can read and copy these reports and
               other information at the public reference facilities maintained
               by the SEC at Room 1024, 450 Fifth Street, NW, Washington, D.C.
               20549. You may obtain copies of this material for a fee by
               writing to the SEC's Public Reference Section of the SEC at 450
               Fifth Street, NW, Washington, D.C. 20549. You may obtain
               information about the operation of the Public Reference Room by
               calling the SEC at 1-800-SEC-0330. You can also access some of
               this information electronically by means of the SEC's website on
               the Internet at http://www.sec.gov, which contains reports, proxy
               and information statements and other information that the
               underlying securities issuer has filed electronically with the
               SEC.

               Although we have no reason to believe the information concerning
               the guarantee, the junior subordinated debentures and the
               underlying securities or the underlying securities guarantor and
               the underlying securities issuer contained in the underlying
               securities guarantor's Exchange Act reports is not reliable,
               neither the depositor nor the trustee participated in the
               preparation of such documents or made any due diligence inquiry
               with respect to the information provided therein. No
               investigation with respect to the underlying securities guarantor
               and underlying securities issuer (including, without limitation,
               no investigation as to their respective financial condition or
               creditworthiness) or of the underlying securities, the junior
               subordinated debentures or the guarantee has been made. You
               should obtain and evaluate the same information concerning the
               underlying securities issuer and the underlying securities
               guarantor as you would obtain and evaluate if your investment
               were directly in the underlying securities or in other securities
               issued by the underlying securities issuer or the underlying
               securities guarantor. There can be no assurance that events
               affecting the underlying securities, junior subordinated
               debentures and guarantee or the underlying securities issuer and
               underlying securities guarantor have not occurred or have not yet
               been publicly disclosed which would affect the accuracy or
               completeness of the publicly available documents described above.

     Item 2.   Properties

               None.

     Item 3.   Legal Proceedings

               None.


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     Item 4.   Submission of Matters to a Vote of Security Holders

               None.

     PART II

     Item 5.   Market for Registrant's Common Equity and Related Stockholder
               Matters

               The Trust Certificates issued by PreferredPLUS Trust Series ALL-1
               are represented by one or more physical certificates registered
               in the name of Cede & Co., the nominee of the Depository Trust
               Company. The Trust Certificates are listed on the New York Stock
               Exchange.

     Item 6.   Selected Financial Data

               Not Applicable.

     Item 7.   Management's Discussion and Analysis of Financial Condition and
               Results of Operations

               Not Applicable.

     Item 7A.  Quantitative and Qualitative Disclosures About Market Risk

               Not Applicable.

     Item 8.   Financial Statements and Supplementary Data

               Not Applicable.

     Item 9.   Changes in and Disagreements With Accountants on Accounting and
               Financial Disclosure

               None.

     Item 9A.  Controls and Procedures

               The Registrant's current report on Form 8-K filed with the
               Securities and Exchange Commission on April 17, 2003 was filed
               late. The principal and notional balances of the Class A and the
               Class B trust securities, respectively, as set forth in the
               distribution reports attached thereto as Exhibits 99.1 to the
               Forms 8-K filed with the Securities and Exchange Commission on
               April 17, 2003 and August 26, 2003 were incorrect, therefore such
               Forms 8-K which contained the incorrect principal and


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               notional balances were subsequently amended on Forms 8-K/A and
               filed with the Securities and Exchange Commission on March 1,
               2004 in order to rectify such errors. The Registrant's annual
               report on Form 10-K filed with the Securities and Exchange
               Commission on January 26, 2004 for the fiscal year ended December
               31, 2003, and as amended hereby, did not include as an exhibit
               (i) a trustee report on compliance with the Standard Terms for
               Trust Agreements dated February 20, 1998, as amended, between the
               Registrant and the Trustee, (ii) an independent accountants'
               report attesting to management's assertion that the Registrant
               complied with its PPLUS Minimum Servicing Standards and (iii) a
               certification by the chief executive officer of the Registrant
               certifying to such compliance with servicing standards. The
               Registrant has revised its procedures so as to provide reasonable
               assurance that its future Exchange Act filings will be filed
               within the applicable time periods.

     PART III

     Item 10.  Directors And Executive Officers Of The Registrant

               Not Applicable.

     Item 11.  Executive Compensation

               Not Applicable.

     Item 12.  Security Ownership of Certain Beneficial Owners and Management
               and Related Stockholder Matters

               (a) Securities Authorized For Issuance Under Equity
                   Compensation Plans: None.
               (b) Security Ownership Of Certain Beneficial Owners: None.
               (c) Security Ownership Of Management: Not Applicable.
               (d) Changes In Control: None.

     Item 13.  Certain Relationships and Related Party Transactions

               None.

     Item 14.  Principal Accounting Fees and Services

               Not Applicable.

     PART IV

     Item 15.  Exhibits, Financial Statement Schedules and Reports on Form 8-K

               (a)(1) Financial Statements: Not Applicable


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               (a)(2) Financial Statement Schedules: Not Applicable

               (a)(3) List of Exhibits

               The following exhibits are filed as part of, and incorporated by
               reference into, this Amendment No. 1 on Form 10-K/A to the
               Registrant's Annual Report on Form 10-K:

                    31.1 Certification of President of Registrant dated March
                         30, 2004, pursuant to Rules 13a-14 and 15d-14 under the
                         Securities Exchange Act of 1934, as adopted pursuant to
                         Section 302 of the Sarbanes-Oxley Act of 2002, with
                         respect to the Registrant's Annual Report on Form 10-K
                         for the year ended December 31, 2003.

                    99.1. Trustee's Annual Compliance Certificate dated March
                          30, 2004.

                    99.2. Independent Accountants' Report dated March 30, 2004,
                          Management's Assertion on Compliance with PPLUS
                          Minimum Servicing Standards dated March 30, 2004 and
                          PPLUS Minimum Servicing Standards.

          (b)  Reports on Form 8-K

               Trustee's report in respect of the February 18, 2003 distribution
               to holders of the PreferredPLUS Trust Certificates Series ALL-1
               incorporated herein by reference as Exhibit 99.1 to Registrant's
               Current Report on Form 8-K filed with the Securities and Exchange
               Commission on April 17, 2003 as amended on Form 8-K/A filed with
               the Securities and Exchange Commission on March 1, 2004.

               Trustee's report in respect of the August 15, 2003 distribution
               to holders of the PreferredPLUS Trust Certificates Series ALL-1
               incorporated herein by reference as Exhibit 99.1 to Registrant's
               Current Report on Form 8-K filed with the Securities and Exchange
               Commission on August 26, 2003.

          (c)  Exhibits

               The Registrant hereby files as part of this Amendment No. 1 on
               Form 10-K/A to its Annual Report on Form 10-K the exhibits listed
               in Item 15(a)(3) set forth above.


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                                   SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, hereunto duly authorized.

                                              MERRILL LYNCH DEPOSITOR, INC.

Date: March 30, 2004                          By:    /s/ Michael Frank Connor
                                                 -------------------------------
                                                   Name:    Michael Frank Connor
                                                   Title:   President