PROPOSED SUPPLEMENTAL INDENTURE

CWCAPITAL COBALT II, LTD.

CWCAPITAL COBALT II, LLC

Resignation of Trustee and Proposed Supplemental Indenture

Reference is made to (i) that certain Indenture dated as of May 10, 2006 (as amended, modified or supplemented through the date hereof, the “Indenture”) among CWCapital Cobalt II, Ltd., as Issuer (the “Issuer”), CWCapital Cobalt II, LLC, as Co-Issuer (the “Co-Issuer”), CWCapital Investments LLC, as Advancing Agent (the “Advancing Agent”) and Wells Fargo Bank, National Association (“Wells Fargo”), as Trustee (the “Trustee”) and (ii) that certain Securities Account Control Agreement dated as of May 10, 2006 (the “Account Control Agreement”) among the Issuer, the Trustee, and Wells Fargo as securities intermediary (the “Securities Intermediary”).

Pursuant to Section 6.9(b) of the Indenture, the Trustee may resign at any time by giving written notice thereof to the Issuer, the Co-Issuer, the Class A-1AR Note Agent, each Hedge Counterparty, the Upfront Swap Counterparty, each Synthetic Asset Counterparty, the Noteholders and each Rating Agency. Wells Fargo, as Trustee (the Outgoing Trustee”) hereby provides you notice pursuant to Section 6.9(b) of the Indenture that it is resigning as Trustee under the Indenture.

You are further notified that U.S. Bank National association has been proposed to be the successor Trustee (the “Successor Trustee”) under the Indenture and will assume all of the Outgoing Trustee’s duties and obligations pursuant to a written agreement, which assumption of duties shall become effective only upon the appointment of the Successor Trustee, the satisfaction of each of the conditions set forth in Section 6.9 and 6.10 of the Indenture, and the Proposed supplement (as defined below) becoming effective.

Notwithstanding the resignation of the Outgoing trustee, Wells Fargo shall continue to act (i) as Paying Agent, Calculation Agent, Transfer Agent, Backup Advancing Agent and Notes Registrar under the Indenture, (ii) as Preferred Shares Paying Agent under the Indenture and Preferred Shares Paying Agency Agreement, (iii) as Custodial Securities Intermediary under the Indenture and Securities Account Control Agreement, as amended in connection with the appointment of the Successor Trustee, and (iv) as Collateral Administrator pursuant to the Indenture, as supplemented by the Proposed supplement as defined below (collectively the “Retained Capacities”), and the Successor Trustee will not assume any of Wells Fargo’s obligations in the Retained Capacities.

You are further notified of a proposed supplement to the Indenture (the “Proposed Supplement”) pursuant to Section 8.1 (d) of the Indenture to evidence and provide for Wells Fargo’s continuing rights and obligations in the Retained Capacities. A copy of the Proposed Supplement is attached hereto as Exhibit B.

The Proposed Supplement shall be entered into with the written consent of each Hedge Counterparty, each Synthetic Asset Counterparty, the Upfront Swap Counterparty and the Collateral Manager, and upon receipt of written confirmation from each Rating Agency that the ratings on the Notes shall not be reduced, qualified or withdrawn as a result of the Proposed Supplement. In addition, the Securities Account Control Agreement shall be amended to evidence and provide for Wells Fargo’s continuing rights and obligations in the Retained Capacities.

All questions may be directed to the attention of Cheryl Bohn by telephone at (410) 884-2097, by email at Cheryl.Bohn@wellsfargo.com, by facsimile at (866) 373-0261 or by mail address to Wells Fargo Bank, National Association, Specialized Asset Service, 9062 Old Annapolis Road, Columbia, MD 21045, Attn: Cheryl Bohn. The Trustee makes no recommendations and gives no investment advice herein or as to the Notes generally.

WELLS FARGO BANK, NATIONAL ASSOCIATION,

As Trustee