# EXHIBIT 31.2

# CERTIFICATION PURSUANT
TO SECTION 302(A)OF THE SARBANES-OXLEY ACT OF 2002

I, Nick Bonos, certify
that:

1.              I
have reviewed the Annual Report on Form 10-K for the fiscal year ended October
          31, 2006 of CurrencySharesSM Mexican Peso Trust;

2.              Based
on my knowledge, this 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 report;

3.              Based
on my knowledge, the financial statements, and other financial information
          included in this 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 report;

4.              The
other certifying officer and I are responsible for establishing and           maintaining
disclosure controls and procedures (as defined in Exchange Act Rules           13a-15(e)
and 15d-15(e)) for the registrant and 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 report is being prepared;

(b)        Evaluated
the effectiveness of the registrants disclosure controls and           procedures
and presented in this 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 (the registrants fourth fiscal quarter in the case of an
          annual report) that has materially affected, or is reasonably likely to
          materially affect, the registrants internal control over financial
          reporting; and

5.              The
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 PADCO Advisors II, Inc.s auditors and the
          board of directors of PADCO Advisors II, Inc. and the board of directors of
          Rydex Fund Services, Inc. and the audit committee of Rydex Specialized Products
          LLCs board of managers (or persons performing equivalent functions):

(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

(b)          Any
fraud, whether or not material, that involves persons who have a significant
          role in the registrants internal control over financial reporting.

Date: January 29, 2007

/s/ Nick Bonos Nick BonosChief
Financial Officer(principal financial officer)