ITC^DELTACOM, INC. EXECUTIVE STOCK INCENTIVE PLAN COMMON STOCK UNIT AGREEMENT (SERIES B PREFERRED STOCK UNIT AGREEMENT, AS AMENDED)

Exhibit 10.21

ITC^DELTACOM, INC.

EXECUTIVE STOCK INCENTIVE PLAN

COMMON STOCK UNIT AGREEMENT

(SERIES B PREFERRED STOCK UNIT AGREEMENT, AS AMENDED)

ITC^DeltaCom, Inc., a Delaware corporation (the “Company”) has previously granted              stock units relating to shares of its 8% Series B Convertible Redeemable Preferred Stock, $.01 par value, to the individual named below as holder pursuant to a Series B Preferred Stock Unit Agreement dated as of December 23, 2005 (the “Preferred Stock Unit Agreement”). In connection with the recapitalization of the Company on July 31, 2007, the Company hereby amends and replaces the Preferred Stock Unit Agreement with this agreement and hereby converts the stock units described above into stock units relating to shares of its common stock, $.01 par value (the “Stock”), subject to the vesting conditions referred to in the attachment. Additional terms and conditions of the grant are set forth in this cover sheet, in the attachment, in the individual’s employment agreement, dated as of                      and as amended as of                      (as further amended from time to time, the “Employment Agreement”), and in the ITC^DeltaCom, Inc. Executive Stock Incentive Plan (the “Plan”).

Grant Date:                                 

Name of Holder:                                 

Holder’s Social Security Number:                                 

Number of Stock Units Covered by Xxxxx:                                

This Stock Unit grant is subject to all of the terms and conditions described in this Agreement and in the Plan, a copy of which is available for your review on the Company’s intranet or upon request to Human Resources. You should carefully review the Plan, and agree that the Plan will control in the event any provision of this Agreement should appear to be inconsistent with the terms of the Plan.

Company:

(Signature)

Title:

Attachment

This is not a stock certificate or a negotiable instrument.

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Attachment

ITC^DELTACOM, INC.

EXECUTIVE STOCK INCENTIVE PLAN

COMMON STOCK UNIT AGREEMENT

(SERIES B PREFERRED STOCK UNIT AGREEMENT, AS AMENDED)

Stock Unit Transferability		This grant is an award of stock units in the number of units set forth on the cover sheet, subject to the vesting conditions described below (the “Stock Units”). Your Stock Units may not be transferred, assigned, pledged or hypothecated, whether by operation of law or otherwise, nor may the Stock Units be made subject to execution, attachment or similar process.
Definitions		Capitalized terms not defined in this Agreement are defined in the Plan, and have the meanings set forth in the Plan. The following additional term has the meaning provided below: “Service” means service by you as an employee of the Company or one of its Affiliates. A change in your position or duties will not result in interrupted or terminated Service so long as you continue to be an employee of the Company or one of its Affiliates.
Vesting		You will vest in the Stock Units in accordance with the terms and conditions contained in your Employment Agreement and the Plan. The resulting aggregate number of vested Stock Units will be rounded down to the nearest whole number of Stock Units. You may not vest in more than the number of Stock Units covered by this grant.
Delivery of Stock Pursuant to Vested Stock Units		Delivery of the shares of Stock represented by your vested Stock Units will be made in accordance with your deferral election attached hereto as Exhibit A, which reflects the deferral election that was in place with respect to your Preferred Stock Unit Agreement prior to its amendment. You will have no further rights with regard to a Stock Unit once the share of Stock relating to the Stock Unit has been delivered.
Forfeiture of Unvested Stock Units		Unvested Stock Units will be forfeited, if at all, in accordance with the terms of the Plan and your Employment Agreement.
Withholding Taxes		You agree, as a condition of this grant, that you will make acceptable arrangements to pay in cash any withholding or

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		other taxes that may be due as a result of vesting in Stock Units or your acquisition of Stock under this grant. In the event that the Company determines that any federal, state, local or foreign tax or withholding payment is required relating to this grant, the Company will have the right to: (i) require that you make such payments to the Company; (ii) withhold such amounts from other payments due to you from the Company or any Affiliate; or (iii) cause an immediate forfeiture of shares of Stock represented by Stock Units granted pursuant to this Agreement in an amount equal to the withholding or other taxes due.
Retention Rights		This Agreement does not give you the right to be retained by the Company (or any Affiliates) in any capacity. The Company (and any Affiliate) reserve the right to terminate your Service at any time and for any reason.
Stockholder Rights		You do not have any of the rights of a stockholder with respect to the Stock Units unless and until the Stock relating to the Stock Units has been delivered to you. You will, however, be entitled to receive, at the same time as the Company’s payment of a cash dividend on outstanding Stock, a cash payment for each Stock Unit that you hold as of the record date for such dividend equal to the per-share dividend paid on the Stock.
Adjustments		In the event of a Capitalization Change or Corporate Transaction, your Stock Units will be adjusted, if at all, in accordance with the terms of the Plan.
Applicable Law		This attachment (including the exhibit attached hereto) and its cover sheet (collectively, this “Agreement”) will be interpreted and enforced under the laws of the State of Delaware, other than any conflicts or choice of law rule or principle that might otherwise refer construction or interpretation of this Agreement to the substantive law of another jurisdiction.
The Plan		The text of the Plan is incorporated in this Agreement by reference. This Agreement, the Plan and your Employment Agreement constitute the entire understanding between you and the Company regarding this grant of Stock Units. Any prior agreements, commitments or negotiations concerning this grant are superseded.

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