<DOCUMENT>
<TYPE>EX-99.906CERT
<SEQUENCE>4
<FILENAME>y60279exv99w906cert.txt
<DESCRIPTION>EX-99.906CERT: CERTIFICATIONS
<TEXT>
<PAGE>

                            SECTION 906 CERTIFICATION

                Certification Pursuant to 18 U.S.C. Section 1350,
                             As Adopted Pursuant to
                  Section 906 of the Sarbanes-Oxley Act of 2002

Morgan Stanley Municipal Income Opportunities Trust

     In connection with the Report on Form N-CSR (the "Report") of the
above-named issuer for the period ended May 31, 2008 that is accompanied by this
certification, the undersigned hereby certifies that:

1.   The Report fully complies with the requirements of Section 13(a) or 15(d)
     of the Securities Exchange Act of 1934; and

2.   The information contained in the Report fairly presents, in all material
     respects, the financial condition and results of operations of the Issuer.


Date: July 31, 2008                          /s/ Ronald E. Robison
                                             -----------------------------------
                                             Ronald E. Robison
                                             Principal Executive Officer

A signed original of this written statement required by Section 906 has been
provided to Morgan Stanley Municipal Income Opportunities Trust and will be
retained by Morgan Stanley Income Opportunities Trust and furnished to the
Securities and Exchange Commission or its staff upon request.


                                       33

<PAGE>

                            SECTION 906 CERTIFICATION

                Certification Pursuant to 18 U.S.C. Section 1350,
                             As Adopted Pursuant to
                  Section 906 of the Sarbanes-Oxley Act of 2002

Morgan Stanley Municipal Income Opportunities Trust

     In connection with the Report on Form N-CSR (the "Report") of the
above-named issuer for the period ended May 31, 2008 that is accompanied by this
certification, the undersigned hereby certifies that:

1.   The Report fully complies with the requirements of Section 13(a) or 15(d)
     of the Securities Exchange Act of 1934; and

2.   The information contained in the Report fairly presents, in all material
     respects, the financial condition and results of operations of the Issuer.


Date: July 17, 2008                          /s/ Francis Smith
                                             -----------------------------------
                                             Francis Smith
                                             Principal Financial Officer

A signed original of this written statement required by Section 906 has been
provided to Morgan Stanley Municipal Income Opportunities Trust and will be
retained by Morgan Stanley Municipal Income Opportunities Trust and furnished to
the Securities and Exchange Commission or its staff upon request.


                                       34
</TEXT>
</DOCUMENT>
