<Page>

                                                               EXHIBIT 99.(3)(4)

                           Emmet, Marvin & Martin, LLP
                                  120 Broadway
                            New York, New York 10271


                                     July 25, 2003

The Bank of New York
  as Trustee of
  Claymore Securities Defined Portfolios, Series 154,
  Closed-End Senior Loan and Income Portfolio, Series 1

101 Barclay Street
New York, New York  10286

Ladies and Gentlemen:

     We are acting as your counsel in connection with the execution and delivery
by you of a certain Reference Trust Agreement, (the "Trust Agreement") dated as
of today's date between Claymore Securities, Inc., as Depositor (the
"Depositor"), and you, as Trustee, establishing Claymore Securities Defined
Portfolios, Series 154, Closed-End Senior Loan and Income Portfolio, Series 1
(the "Trust"), and the execution by you, as Trustee under the Trust Agreement,
of receipts for units evidencing ownership of all of the units of fractional
undivided interest (such receipts for units and such aggregate units being
herein respectively called "Receipts for Units" and "Units") in the Trust, as
set forth in the prospectus, (the "Prospectus") included in the registration
statement on Form S-6, as amended to the date hereof (the "Registration
Statement"), relating to the Trust. The Trust consists of equity and/or debt
securities (the "Securities") (including delivery statements relating to
contracts for the purchase of certain Securities not yet delivered and cash,
cash equivalents or an irrevocable letter or letters of credit, or a combination
thereof, in the amount required to pay for such purchases upon the receipt of
such Securities) as listed under "Portfolio" in the Prospectus (such Securities,
delivery statements and cash, cash equivalents, letter or letters of credit
being herein called the "Portfolio Assets").

     We have examined the Trust Agreement, and originals (or copies certified or
otherwise identified to our satisfaction) of such other instruments,
certificates and documents as we have deemed necessary or appropriate for the
purpose of rendering this opinion. In such examination, we have assumed the
genuineness of all signatures, the authenticity of all documents submitted to us
as originals and the conformity to the original documents of all documents
submitted to us as copies. As to any facts material to our opinion, we have,
when relevant facts were not independently established, relied upon the
aforesaid instruments, certificates and documents.

     Based on the foregoing, we are of the opinion that:

     1.   The Bank of New York is a corporation organized under the laws of the
State of New York with the powers of a trust company under the Banking Law of
the State of New York.

<Page>

     2.   The Trust Agreement is in proper form for execution and delivery by
you, as Trustee, and each has been duly executed and delivered by you, as
Trustee, and assuming due authorization, execution and delivery by the
Depositor, the Trust Agreement is a valid and legally binding obligation of The
Bank of New York.

     3.   The Receipts for Units are in proper form for execution by you, as
Trustee, and have been duly executed by you, as Trustee, and pursuant to the
Depositor's instructions, the Trustee has registered on the registration books
of each of the Trust the ownership of the Units by Cede & Co., as nominee of the
Depository Trust Company where it has caused the Units to be credited to the
account of the Depositor.

     In rendering the foregoing opinion we have not considered, among other
things, the merchantability of the Portfolio Assets, whether the Portfolio
Assets have been duly authorized and delivered or the tax status of the
Portfolio Assets under any federal, state or local laws.

     We are members of the New York Bar only and do not hold ourselves out as
experts on, nor do we express any opinion as to, the laws of any jurisdiction
other than the laws of the State of New York and the federal laws of the United
States. This opinion is for your benefit and may not be disclosed to or relied
upon by any other person without our prior written consent.

                                     Very truly yours,