EXHIBIT 31.1

I, Stephan Kuppenheimer, certify that:

1. I have reviewed this annual report on Form 10-K, and all reports on Form 8-K
containing distribution or servicing reports filed in respect of periods
included in the year covered by this annual report, of Merrill Lynch Depositor,
Inc., on behalf of INDEXPLUS Trust Series 2003-1;

2. Based on my knowledge, the information in these reports, taken as a whole,
does not contain any untrue statement of a material fact or omit to state a
material fact necessary to make the statements made, in light of the
circumstances under which such statements were made, not misleading as of the
last day of the period covered by this annual report;

3. Based on my knowledge, the distribution or servicing information required to
be provided to the depositor by the trustee under the pooling and servicing, or
similar, agreement, for inclusion in these reports is included in these reports;

4. I am responsible for reviewing the activities performed by the depositor and
the trustee under the pooling and servicing, or similar, agreement and based
upon my knowledge and the annual compliance review required under that
agreement, and except as disclosed in the reports, the depositor and trustee
have each fulfilled its obligations under that agreement; and

5. The reports disclose all significant deficiencies relating to the compliance
by the depositor or trustee with the minimum servicing or similar standards
based upon the report provided by an independent public accountant, after
conducting a review in compliance with the Uniform Single Attestation Program
for Mortgage Bankers or similar procedure, as set forth in the pooling or
servicing, or similar, agreement, that is included in these reports.

In giving the certifications above, I have reasonably relied on information
provided to me by the following unaffiliated parties: The Bank of New York and
its officers and agents.


Date:  March 29, 2005                      /s/ Stephan Kuppenheimer
                                          --------------------------------
                                           President