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EXHIBIT 10.37

AMENDMENT NO. 1
TO INTERCONNECTION AGREEMENT
BY AND BETWEEN
SOUTHWESTERN BELL TELEPHONE COMPANY
AND
BIRCH TELECOM OF OKLAHOMA, INC.

    The Interconnection Agreement ("the Agreement") by and between Southwestern
Bell Telephone Company ("TELCO") and Birch Telecom of Oklahoma, Inc. ("CLEC") is
hereby amended as follows:

    (1) Addition of Appendix Oklahoma Alternative Regulation Transition Plan

    (2) Table of Contents modified to add additional Appendix

    (3) This Amendment shall not modify or extend the Effective Date or Term of
the underlying Agreement, but rather, contains a termination date specific to
the Appendix Oklahoma Alternative Regulation Transition Plan adopted into the
Interconnection Agreement which may or may not be coterminous with the
underlying Agreement.

    (4) EXCEPT AS MODIFIED HEREIN, ALL OTHER TERMS AND CONDITIONS OF THE
UNDERLYING AGREEMENT SHALL REMAIN UNCHANGED AND IN FULL FORCE AND EFFECT, and
such terms are hereby incorporated by reference and the Parties hereby reaffirm
the terms and provisions thereof.

    (5) This Amendment shall be filed with and is subject to approval by the
Oklahoma Corporations Commission and shall become effective upon approval of the
Commission.

    IN WITNESS WHEREOF, this Amendment to the Agreement was exchanged in
triplicate on this 15th day of June, 2000, by TELCO, signing by and through its
duly authorized representative, and CLEC, signing by and through its duly
authorized representative.

BIRCH TELECOM OF OKLAHOMA, INC.   SOUTHWESTERN BELL TELEPHONE COMPANY  
   
   
   
By: SBC Telecommunications, Inc.,       Its authorized agent  
By:  
/s/ RINA HARTLINE   

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By:  
/s/ WILLENA D. SLOCUM   

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Title: Director State Regulation

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  Title: President—Industry Markets

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Name: Rina Hartline

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(Print or Type)   Name: Willena D. Slocum

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(Print or Type)

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QUICKLINKS

EXHIBIT 10.37
AMENDMENT NO. 1 TO INTERCONNECTION AGREEMENT BY AND BETWEEN SOUTHWESTERN BELL
TELEPHONE COMPANY AND BIRCH TELECOM OF OKLAHOMA, INC.