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EXHIBIT 99.10(a)
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the reference to our firm under the captions "Financial
Highlights" in the Prospectus, and "Independent Auditors and Financial
Statements" in the Statement of Additional Information and to the incorporation
by reference in this Post-Effective Amendment No. 13 to Registration Statement
No. 33-68310 on Form N-1A of our report dated November 9, 2000, on the financial
statements and financial highlights of Vertex All Cap Fund and Vertex Contrarian
Fund, each a series of MFS Series Trust XI, included in the 2000 Annual Report
to Shareholders.
ERNST & YOUNG LLP
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Ernst & Young LLP
Boston, Massachusetts
November 24, 2000
