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                                                                    EXHIBIT 31.2

I, Thomas G. Mackay, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Mills Music Trust;

2. Based on my knowledge, this quarterly report 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 with respect to the period covered by this quarterly
report;

3. Based on my knowledge, the financial statements, and other financial
information included in this quarterly report, fairly present in all material
respects the financial condition, results of operations and cash flows of the
registrant as of, and for, the periods presented in this quarterly report; *

4. The registrant's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15e and 15d-15e) for the registrant and we have:

     a) designed such disclosure controls and procedures, or caused such
     disclosure controls and procedures to be designed under our supervision, to
     ensure that material information relating to the registrant, including its
     consolidated subsidiaries, is made known to us by others within those
     entities, particularly during the period in which this quarterly report is
     being prepared;

     b) evaluated the effectiveness of the registrant's disclosure controls and
     procedures and presented this quarterly report our conclusions about the
     effectiveness of the disclosure controls and procedures, as of the end of
     the period covered by this report based on such evaluation; and

     c) disclosed in this report any change in the registrant's internal control
     over financial reporting that occurred during the registrant's most recent
     fiscal quarter that has materially affected, or is reasonably likely to
     materially affect, the registrant's internal control over financial
     reporting; and

5. The registrant's other certifying officer and I have disclosed, based on our
most recent evaluation of internal control over financial reporting, to the
registrant's auditors and the audit committee of registrant's board of directors
(or persons performing the equivalent function):

     a) all significant deficiencies and material weaknesses in the design or
     operation of internal control over financial reporting which are reasonably
     likely to adversely affect the registrant's ability to record, process,
     summarize and report financial information; and

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Date: November 14, 2007                 /s/ Thomas G. Mackay
                                        ----------------------------------------
                                        Thomas G. Mackay
                                        Trust officer of The Corporate Trustee

*    The statements of cash receipts and disbursements reflect only cash
     transactions and do not include transactions that would be recorded in
     financial statements presented on the accrual basis of accounting. The
     Trust is required to distribute all funds received. Accordingly, the Trust
     has not prepared any statements of financial condition or cash flows.