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                                                                 EXHIBIT 2.5.2.2
                              AMENDED AND RESTATED
                                      11.5%
                          SUBORDINATED PROMISSORY NOTE

Principal Amount: $4,456,250                              As of January 11, 2000

         For value received, Able Telcom Holding Corp. ("Able") hereby agrees to
pay to the order of WorldCom Network Services, Inc., its successors or assigns
("WorldCom"), in lawful money of the United States of America and immediately
available funds, at its offices in Tulsa, Oklahoma (or at such other place or
places WorldCom may designate) the principal amount of Four Million Four Fifty
Six Thousand Two Hundred Fifty and No/l00 Dollars ($4,456,250) on February 1,
2001 ("Maturity Date"). Subject to the subordination terms herein, all principal
and accrued interest shall be payable on the Maturity Date.

1.  DEFINITIONS

         1.1  "AGENT" means the Administrative Agent under that certain Credit
Agreement, dated as of July 11, 1998, among NationsBank, as Administrative
Agent, Able, and the Several Lenders from time to time parties thereto, as the
same may be or may have been amended, restated, modified, renewed or replaced
from time to time (the "Credit Agreement").

         1.2  "BANKS" means the lenders from time to time identified as a
"Lender" in the Credit Agreement.

         1.3  "BORROWER" shall have the meaning given in the Credit Agreement.

         1.4  "OBLIGATIONS" shall have the meaning given in the Credit
Agreement.

         1.5  "SUBORDINATED DEBT" shall mean at any time, all principal of and
interest on and premiums (if any) related to this Subordinated Promissory Note
and any collateral securing the payment of the same.

         1.6 "SUPERIOR DEBT" shall mean the Obligations of the Borrower under
the Credit Agreement, including all principal of and interest on and premiums
(if any) related thereto and any collateral securing the payment of the same.

2.       AMENDMENT This Amended and Restated Subordinated Note amends and
restates that certain subordinated promissory note of Able dated as of September
1,1998, payable to the order of WorldCom in the principal amount of $30,000,000
(the "Prior Note"), which replaced that certain unsubordinated promissory note
of Able dated as of September 1,1998, payable to the order of WorldCom in the
principal amount of $30,000,000, which replaced that certain promissory note of
Able dated as of July 2, 1998, payable to the order of MFS Communications
Corporation, Inc. in the original principal amount of $86,405,217, all three of
which have been cancelled.


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3.       SUBORDINATION.

         3.1      Able and WorldCom (the "Subordinated Lender") acknowledge and
agree that notwithstanding anything to the contrary herein, at all times, the
principal amount of any outstanding debt of Able to the Subordinated Lender
shall be subordinated to the Superior Debt. Until the indefeasible payment in
full of the Superior Debt: (a) the payment of the principal amount or fees and
premiums, if any (including payments of interest), on all Subordinated Debt
shall be subordinated to the payment in full of all Superior Debt; (b) Able will
not make and the Subordinated Lender will not take or receive from Able, in any
manner, payment of the whole or any part of the principal of and interest on and
fees and premiums, if any, of the Subordinated Debt; and (c) the Subordinated
Lender will not take any action towards the enforcement of any liens in respect
of any or all of the Subordinated Debt, or exercise any rights granted under
such liens in respect of the collateral subject thereto.

         3.2      Upon any distribution of assets of Able to its creditors upon
any dissolution, winding-up, total or partial liquidation, readjustment of debt,
reorganization or similar proceeding of Able or its property, or in any
bankruptcy, insolvency, receivership, assignment for the benefit of creditors,
marshaling of assets and liabilities of Able, or other proceeding, whether any
of the foregoing is voluntary or involuntary, partial or complete, all amounts
due on the Superior Debt including all interest, fees and costs of collections,
including attorneys' fees and expenses shall first be paid in full before the
Subordinated Lender shall be entitled to receive or retain any payment or
distribution from Able in respect of the Subordinated Debt.

         3.3      Notwithstanding the foregoing paragraphs and without any
derogation thereof, if upon any such dissolution, winding-up, liquidation,
readjustment, reorganization or other proceeding, any payment or distribution of
assets or securities of Able of any kind or character, whether in cash, property
or securities, shall be received by the Subordinated Lender in respect of the
Subordinated Debt before all the Superior Debt is indefeasibly paid in full,
such payment or distribution will be held in trust for the benefit of, and shall
promptly be paid over in trust for the benefit of, and in the form received
(duly endorsed, if necessary, to the holders of the Superior Debt) to the
holders of the Superior Debt (or their appointed trustee or agent) for
application to the payment of the Superior Debt until all the Superior Debt
shall have been paid in full.

4.       INTEREST.

         4.1      Interest on the unpaid principal amount hereof from time to
time shall accrue at an annual rate of 11.5% from the date hereof. Interest
hereunder shall be computed on the basis of the actual number of days elapsed
over a year of 360 days.

         4.2      Any amount hereunder that becomes due on a Saturday, Sunday or
other day when banks in New York are not open for business shall be payable on
the next business day when such banks are open for business (a "Business Day")
with interest accruing until the date of payment.


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         4.3      If any amount owned by Able hereunder is not paid when due,
such amount will bear interest at a rate equal to 13.5% per annum (the "Default
Rate"), payable on demand by WorldCom. Nothing herein contained shall be
construed or so operate as to require Able to pay any interest, fees, costs or
charges at a rate or in an amount greater than is permitted by applicable law.

         4.4      Upon a default in payment of principal, interest or other
amounts owing hereunder when due, the unpaid principal amount of this
subordinated note, together with all accrued but unpaid interest thereon, may
become, or may be declared to be, (and in the case of a bankruptcy or insolvency
proceeding naming Able as debtor, shall, without action on the part of WorldCom,
become), immediately due and payable, without presentation, demand, protest or
notice of any kind, all of which are hereby waived by Able.

         4.5      Able agrees to pay on demand all direct out-of-pocket losses,
and reasonable out-of-pocket costs and expenses, if any (including reasonable
fees and expenses of outside counsel), of WorldCom in connection with the
enforcement (whether by legal proceedings, negotiation or otherwise) of this
Subordinated Note and other documents delivered hereunder.

         4.6      Upon the occurrence and during the continuance of any default
hereunder, but subject to the subordination provisions hereof, WorldCom is
hereby authorized at any time and from time to time, to the fullest extent
permitted by law, to set off and apply any and all amounts of other indebtedness
at any time owning by WorldCom to or for the credit or the account of Able
against any and all of the obligations of Able now or hereafter existing under
this Note, irrespective of whether or not WorldCom shall have made any demand
under this Note and of whether or not such obligations may be matured. Such set
off amounts shall be applied first to principal and then to interest. WorldCom
agrees promptly to notify Able and the Agent after such set off and application
made by WorldCom, but the failure to give such notice shall not affect the
validity of such set-off and application subject to all liens in favor of the
Agent or the Banks. The rights of the WorldCom under this paragraph are in
addition to other rights and remedies (including, without limitation, other
rights of set-off) which WorldCom may have and are subject to any rights any
holders of Superior Debt may have.

5.       NO PREPAYMENT. No principal hereof or interest thereon shall be
prepayable.

6.       WAIVER.

         6.1      In the event this Subordinated Note is transferred, assigned
or pledged, Able hereby waives, as against such transferee, assignee or pledges,
any defenses and counterclaim that Able may have against the prior holder
hereof.

         6.2      The Subordinated Lender hereby waives: (i) notice of
acceptance by the holders of the Superior Debt hereof, (ii) notice of the
existence or creation or nonpayment of all or any of the Superior Debt; and
(iii) all diligence in collection or protection of or realization upon the
Superior Debt or any thereof or any security therefor.


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7.       NO IMPAIRMENT OF RIGHTS. Nothing herein contained shall impair, as
between Able and the Subordinated Lender, the obligation of Able, which
(although it is restricted hereby) is absolute and, unconditional, to make
payments of the Subordinated Debt as and when the same shall become due and
payable in accordance with its terms (as restricted hereby), or affect the
relative rights of the Subordinated Lender and creditors of Able other than
holders of Superior Debt.

8.       BINDING AGREEMENT. The provisions hereof shall be binding upon the
Subordinated Lender and Able and upon their successors. All references to Able
and the Subordinated Lender, respectively, shall be deemed to include their
respective successors, whether immediate or remote, and all references to Able
and the Subordinated Lender shall be deemed to include their respective
subsidiaries.

9.       CHOICE OF LAW, VENUE. Any suit, action or proceeding arising out of or
in connection with the provisions hereof relating to subordination may be
brought against Able or the Subordinated Lender in a court in Florida of record
of the State of Florida, or a United States District Court sitting in Florida
and each of the Able and the Subordinated Lender hereby irrevocably submits and
consents to the jurisdiction of each such court and agrees that any summons,
complaint, writ, judgment or other notice or service of legal process may be
sufficiently served upon it in connection with any such suit, action or
proceeding. In any suit, action or proceeding relating to the subordination
hereunder, each of Able and the Subordinated Lender waives, to the fullest
extent not prohibited by applicable law, any objection which it may now or
hereafter have to the laying of the venue of any suit, action or proceeding
brought in such court and any claim that the same was brought in an inconvenient
forum. The submission to the said jurisdiction shall not (and shall not be
construed so as to) limit the right of the holders of the Superior Debt, or any
of them, or any agent on their behalf, to take proceedings against Able or the
Subordinated Lender This Subordinated Note shall be governed by and construed in
accordance with the laws of the state of Florida without regard to conflicts of
law provisions thereof.

10.      SURVIVAL. If any provision or obligations of the Subordinated Note
shall be determined to be invalid, ineffective of unenforceable, the validity,
effectiveness and enforceability of the remaining provisions or obligations
shall not in way be affected or impaired thereby.

11.      RELATION TO AGREEMENT. This Amended and Restated Subordinated Note is
the "Subordinated Note" referred to in the Amended and Restated Agreement
Regarding Promissory Note, dated as of April 1, 1999 (the "Related Agreement"),
between Able and WorldCom which provides, among other things, for the source of
payments hereon subject to the subordination provisions hereof and thereof.

12.      ENTIRE AGREEMENT. THIS AMENDED AND RESTATED SUBORDINATED NOTE, TOGETHER
WITH THE RELATED AGREEMENT, REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES
AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT
ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN
THE PARTIES.

                            [Signature page follows]


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         IN WITNESS WHERE OF, Able has caused this Subordinated Note to be
executed and delivered by its duly authorized officer as of the date first above
written.

                                             ABLE TELCOM HOLDING CORP.



                                             By:
                                                --------------------------------
                                             Title:
                                                   -----------------------------

         IN WITNESS WHERE OF, WorldCom hereby affirms by execution below,
WorldCom's agreement to the terms and conditions stated herein, reaffirms the
Subordination provisions of Section 3 hereof and waives any rights WorldCom may
have had under the Prior Note in exchange for the rights provided WorldCom under
this Amended and Restated Subordinated Note.
                                             WORLDCOM NETWORK SERVICES, INC.



                                             By:
                                                --------------------------------
                                             Title:
                                                   -----------------------------


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