**FOURTH
        AMENDMENT**
 **TO**
 **LOAN
        AND SECURITY AGREEMENT**
 
  
  This
        Fourth Amendment to Loan and Security Agreement (this "Amendment") is dated
        as
        of July 31, 2006, by and between COMERICA BANK ("Bank") and PAC-WEST TELECOMM,
        INC., PAC-WEST TELECOM OF VIRGINIA, INC., PWT SERVICES, INC., and PWT OF
        NEW
        YORK, INC. (each a “Borrower” and collectively, “Borrowers”).
  RECITALS
  Borrowers
        and Bank are parties to that certain Loan and Security Agreement dated as
        of
        November 9, 2005 (as amended from time to time, including by that certain
        First
        Amendment to Loan and Security Agreement dated as of November 30, 2005, that
        certain Second Amendment to Loan and Security Agreement dated as of February
        17,
        2006, that
        certain Third Amendment to Loan and Security Agreement dated as of May 30,
        2006 ,
        that
        certain waiver letter dated as of May 11, 2006, together with any related
        agreements, the "Agreement"). The parties desire to amend the Agreement in
        accordance with the terms of this Amendment.
  NOW,
        THEREFORE, the parties agree as follows:
  1.  Notwithstanding
        anything to the contrary in the Agreement, during the period commencing May
        1,
        2006 through and including  September
        30, 2006 ,
        Borrowers shall not be required to comply with Sections 6.7 (a), (c) or (d)
        of
        the Agreement; provided
        that Borrowers remain in compliance with Section 6.7 (b) as amended by this
        Amendment.
  2.  Notwithstanding
        anything to the contrary in the Agreement, during the period commencing July
        1,
        2006 through and including September 30, 2006, the minimum balance of Cash
        at
        Bank required by Section 6.7 (b) to be maintained by Borrowers shall be Two
        Million Five Hundred Thousand Dollars ($2,500,000) in excess of the outstanding
        Indebtedness owed to the Bank.
  3.  Borrowers
        may request additional Credit Extensions from and after such time as Borrowers
        are in pro-forma compliance with Sections 6.7 (a), (b), (c), and (d) of the
        Agreement without
        regard to this Amendment .
  4.  Unless
        otherwise defined, all initially capitalized terms in this Amendment shall
        be as
        defined in the Agreement. The Agreement, as amended hereby, shall be and
        remain
        in full force and effect in accordance with its respective terms and hereby
        is
        ratified and confirmed in all respects. Except as expressly set forth herein,
        the execution, delivery, and performance of this Amendment shall not operate
        as
        a waiver of, or as an amendment of, any right, power, or remedy of Bank under
        the Agreement, as in effect prior to the date hereof.
  5.  Borrowers
        represent and warrant that the Representations and Warranties contained in
        the
        Agreement are true and correct as of the date of this Amendment, and that
        no
        Event of Default has occurred and is continuing.
  6.  As
        a
        condition to the effectiveness of this Amendment, Bank shall have received,
        in
        form and substance satisfactory to Bank, the following:
  (a)  this
        Amendment, duly executed by Borrowers;
  (b)  an
        Amendment fee from the account of the Borrower in the amount of
        $10,000;
  (c)  all
        reasonable Bank Expenses incurred through the date of this Amendment, which
        may
        be debited from any of Borrowers' accounts; and
  (d)  such
        other documents, and completion of such other matters, as Bank may reasonably
        deem necessary or appropriate.
  7.  This
        Amendment may be executed in two or more counterparts, each of which shall
        be
        deemed an original, but all of which together shall constitute one
        instrument.
  
  IN
        WITNESS WHEREOF, the undersigned have executed this Amendment as of the first
        date above written.
  PAC-WEST
                  TELECOMM, INC.By:
                  /s/ Henry CarabelliTitle:
                  CEO & PresidentPAC-WEST
                  TELECOM OF VIRGINIA, INC.By: 
                  /s/ Ravi BrarTitle:
                  COOPWT
                  SERVICES, INC.By:
                  /s/ Ravi BrarTitle:
                  COOPWT
                  OF NEW YORK, INC.By:
                  /s/ Ravi BrarTitle:
                  COOCOMERICA
                  BANKBy:
                  /s/ Rod WernerTitle:
                  SVP