**Exhibit 2.2****AGREEMENT AND PLAN OF MERGER**     This AGREEMENT AND PLAN OF MERGER, dated as of August 2, 2005 (this “Agreement”), is enteredinto by and among UCBH Holdings, Inc., a Delaware corporation registered under the Bank HoldingCompany Act of 1956, as amended (“Buyer”), United Commercial Bank, a California state-charteredbank and a wholly owned subsidiary of Buyer (“UCB”), and Asian American Bank & Trust Company, aMassachusetts state-chartered trust company (the “Company”).     WHEREAS, the Boards of Directors of Buyer, UCB and the Company have determined that it is inthe best interests of their respective companies and their shareholders to consummate the businesscombination transaction provided for herein in which the Company will, subject to the terms andconditions set forth herein, merge with and into UCB, with UCB being the surviving entity (the“Merger”);     WHEREAS, the parties intend for the Merger to constitute a reorganization within the meaningof Section 368(a) of the Internal Revenue Code of 1986, as amended (the “Code”), and theregulations thereunder; and     WHEREAS, the parties desire to make certain representations, warranties and agreements inconnection with the Merger and also to prescribe certain conditions to the Merger.     NOW, THEREFORE, in consideration of the mutual covenants, representations, warranties andagreements contained herein, and intending to be legally bound hereby, the parties agree asfollows:**ARTICLE I****THE MERGER**     1.1 Definitions. The defined terms used in this Agreement have the meanings set forthon Appendix I hereto.     1.2 The Merger. Subject to the terms and conditions of this Agreement, in accordancewith applicable provisions of the CFC, the CGCL, Massachusetts banking laws, the MBCL and theRiegle-Neal Interstate Banking and Branching Efficiency Act of 1994 (the “Interstate Act”), at theEffective Time, the Company shall merge with and into UCB. UCB shall be the surviving corporation(hereinafter sometimes called the “Surviving Corporation”) in the Merger and shall continue itscorporate existence under the laws of the State of California. The name of the SurvivingCorporation shall be “United Commercial Bank.” Upon consummation of the Merger, the separatecorporate existence of the Company shall terminate. The parties hereto hereby adopt this Agreementas a “plan of reorganization” within the meaning of Code Section 368 and the regulationsthereunder.     1.3 Closing; Effective Time.          (a) Closing. Subject to the terms and conditions of this Agreement, the closing ofthe Merger (the “Closing”) will take place at 10:00 a.m. on the last business day of the
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month in which the latest to occur of the conditions set forth in Article VIII hereof (otherthan those conditions which relate to actions to be taken at the Closing) has been waived orsatisfied (subject to applicable law) (provided that if such waiver or satisfaction occurs duringDecember 2005, the Closing will take place on January 31, 2006, and if such waiver or satisfactionoccurs during March 2006, the Closing will take place on April 30, 2006, or such other date as theparties mutually agree) (the “Closing Date”), at the offices of Squire, Sanders & Dempsey L.L.P.,One Maritime Plaza, Suite 300, San Francisco, California 94111-3492 unless another time, date orplace is agreed to in writing by the parties hereto.          (b) Effective Time. Subject to the provisions of this Agreement, an agreement ofmerger complying with Section 1101 of the CGCL and Sections 78 and 85 of the MBCL (the “Agreementof Merger”) and officers’ certificates complying with Section 1103 of the CGCL (the “CaliforniaCertificates”) and Section 4800 *et seq*. of the CFC in substantially the forms attached hereto asExhibit A and Exhibit B, respectively, shall be duly executed and filed with the Secretary of Stateof the State of California (the “California Secretary”) and the Secretary of State of the State ofMassachusetts (the “Massachusetts Secretary”) on the Closing Date by the Company and UCB. TheMerger shall become effective at such time the filings with the California Secretary and theMassachusetts Secretary of the Agreement of Merger are received and accepted by the CADFI (the“Effective Time”).     1.4 Effects of the Merger. At and after the Effective Time, the Merger shall havethe effects set forth in Section 1107 of the CGCL, Section 80 of the MBCL and Section 4800 *et seq*.of the CFC.     1.5 Conversion of Company Common Stock.          (a) At the Effective Time, subject to the exceptions and limitations set forth in Article IIhereof, each share of Company Common Stock issued and outstanding immediately prior to theEffective Time (other than Dissenting Shares), shall, by virtue of this Agreement and without anyaction on the part of the holder thereof, be cancelled and cease to exist and converted into theright to receive, depending upon the election of the holder thereof as provided in Section 2.2hereof, (i) shares of Buyer Common Stock in accordance with the Exchange Ratio, (ii) cash in theamount of the Per Share Cash Consideration, or (iii) a combination of such shares and cash(collectively, the “Merger Consideration”).          (b) Notwithstanding any other provision hereof, no fractional shares of Buyer Common Stockshall be issued to holders of Company Common Stock. In lieu thereof, each such holder otherwiseentitled to a fraction of a share of Buyer Common Stock shall receive, at the time of surrender ofthe Certificate or Certificates, an amount in cash equal to the product of (i) the Per Share CashConsideration and (ii) the fraction of a share of Buyer Common Stock to which such holder otherwisewould be entitled, rounded to the nearest penny. No such holder shall be entitled to dividends,voting rights, interest on the value of, or any other rights in respect of a fractional share,except as expressly provided herein.          (c) Notwithstanding anything in this Agreement to the contrary, shares of Company Common Stockwhich are outstanding immediately prior to the Effective Time and which shareholders have givennotice of their intention to assert dissenters rights under Section
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85 of the MBCL and which shareholders have voted not to approve the Merger (such shares beingreferred to herein as “Dissenting Shares”) shall not be converted into the right to receive theMerger Consideration but, instead, the holders thereof shall be entitled to receive payment of thefair market value of such Dissenting Shares in accordance with the provisions of Section 86 to 98inclusive, of the MBCL (“Section 86 *et seq*.”); provided, however, that (i) if any holder ofDissenting Shares shall subsequently withdraw, with the consent of the Surviving Corporation, hisdemand for purchase of such shares, or (ii) if any holder of Dissenting Shares fails to establishor otherwise loses his entitlement to payment of the fair market value of such shares as providedin Section 86 *et seq*., such holder or holders (as the case may be) shall not be entitled to receivepayment of the fair market value of such shares of Company Common Stock as contemplated by Section86 *et seq*., and each of such shares shall thereupon cease to be Dissenting Shares and shall bedeemed to have been converted into the right to receive, as of the Effective Time, the MergerConsideration without any interest thereon, as provided in Section 1.5(a) and Article II hereof.Prior to the Effective Time, the Company shall give Buyer prompt notice of any demands forappraisal pursuant to Section 86 *et seq.*received by the Company, withdrawals of any such demandsand any other documents or instruments received by the Company in connection therewith. Buyershall have the right to participate in and direct all negotiations and proceedings with respect toany such demands. Prior to the Effective Time, the Company shall not, except with the priorwritten consent of Buyer, which consent shall not unreasonably be withheld or delayed, make anypayment with respect to, or settle or offer to settle, any such demands, or agree to do any of theforegoing.     1.6 Buyer Capital Stock; UCB Capital Stock. Each share of the capital stock of UCBissued and outstanding immediately prior to the Effective Time shall remain outstanding and shallnot be converted or otherwise affected by the Merger, and such shares shall thereafter constituteall of the issued and outstanding shares of the Surviving Corporation. Each share of Buyer CapitalStock issued and outstanding immediately prior to the Effective Time shall remain outstanding andshall not be converted or otherwise affected by the Merger.     1.7 Articles of Incorporation. At the Effective Time, the Articles of Incorporationof UCB, as in effect at the Effective Time, shall be the Articles of Incorporation of the SurvivingCorporation.     1.8 Bylaws. At the Effective Time, the Bylaws of UCB, as in effect immediately priorto the Effective Time, shall be the Bylaws of the Surviving Corporation until thereafter amended inaccordance with applicable law.     1.9 Directors and Officers. The directors and officers of UCB immediately prior tothe Effective Time shall be the directors and officers of the Surviving Corporation, each to holdoffice in accordance with the Articles of Incorporation and Bylaws of the UCB until theirrespective successors are duly elected or appointed and qualified.
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**ARTICLE II****DELIVERY OF MERGER CONSIDERATION**     2.1 Surrender of Company Common Stock.          (a) Prior to the Effective Time, Buyer shall appoint Mellon Investor Services LLC, or itssuccessor, or any other bank or trust company mutually acceptable to Buyer and the Company, asexchange agent (the “Exchange Agent”) for the purpose of exchanging Certificates representingshares of Company Common Stock. At or prior to the Effective Time, Buyer shall deposit with theExchange Agent (i) such number of certificates of Buyer’s Common Stock representing the AggregateBuyer Share Amount and (ii) immediately available funds in an amount not less than the portion ofthe Aggregate Cash Value payable hereunder to holders of Company Common Stock (other thanDissenting Shares) outstanding immediately prior to the Effective Time.          (b) Buyer shall direct the Exchange Agent to mail on the Mailing Date to each holder of recordof a certificate or certificates representing any such shares of Company Common Stock (each, a“Certificate”): (i) a letter of transmittal to be completed, signed and returned to the ExchangeAgent by each such holder, (ii) an Election Form to be completed, signed and returned to theExchange Agent by each such holder, (iii) appropriate and necessary documentation enabling suchholder to establish, if applicable, an exemption from tax withholding in connection with payment ofthe Merger Consideration to each such holder, and (iv) instructions regarding the documentationdescribed in clauses (i) through (iii) above for use in effecting the surrender of theCertificates. The instructions shall specify that (w) Election Forms, properly completed and dulyexecuted, are required to be returned to the Exchange Agent by the Election Deadline, (x) thematerials specified in clauses (i) and (iii) above, properly completed and duly executed, arerequired to be returned to the Exchange Agent, accompanied by one or more Certificates (orcustomary affidavits and indemnification regarding the loss or destruction of such Certificates orthe guaranteed delivery of such Certificates) representing all shares of Company Common Stockcovered by the Election Form submitted by such holder, (y) delivery of the Certificates shall beeffected, and risk of loss and title to the Certificates shall pass, only upon delivery of theCertificates to the Exchange Agent, and (z) upon surrendering a Certificate for cancellation to theExchange Agent or to such other agent or agents as may be appointed by Buyer, together with suchletter of transmittal, duly executed, the holder of such Certificate shall be entitled to receivein exchange therefor the Merger Consideration (subject to the provisions of Section 2.2), and theCertificate so surrendered shall forthwith be canceled.          (c) If any payment of the Merger Consideration for shares of Company Common Stock is to bemade in a name other than that in which the Certificate surrendered in exchange therefor isregistered, it shall be conditions of such payment that the Certificate be presented to theExchange Agent, accompanied by all documents required to evidence and effect the transfer ofownership thereof, and that the person requesting such payment shall pay to the Exchange Agent inadvance any transfer costs and expenses, including taxes, required by reason of the payment of theMerger Consideration to a person other than the registered holder of the Certificate surrendered,or required for any other reason, or shall establish to the satisfaction of the Exchange Agent thatsuch transfer costs and expenses, have been paid or are not payable.
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          (d) Until surrendered as contemplated by this Section 2.1 and except as otherwise providedherein, each Certificate shall be deemed at any time after the Effective Time to represent only theright to receive upon such surrender the Merger Consideration. Notwithstanding anything to thecontrary set forth herein, if any holder of shares of Company Common Stock should be unable tosurrender the Certificates representing such shares, because the Certificates have been lost ordestroyed, upon the making of an affidavit of that fact by the person claiming such Certificates tobe lost, stolen or destroyed and, if required by Buyer, the posting by such person of a bond insuch amount as may be determined to be adequate by Buyer as indemnity against any claim that may bemade against it with respect to such Certificates, such holder shall be entitled to receive theMerger Consideration. No interest shall be paid on any of the Merger Consideration.     2.2 Election and Proration Procedures.          (a) In accordance with Section 2.1(b), an election form (“Election Form”) and the othermaterials specified in Section 2.1(b)(i)-(iv), as well as other appropriate and customarytransmittal materials, in such form as Buyer and the Company shall mutually agree shall be mailedno less than thirty-five (35) days prior to the anticipated Effective Time or on such other date asthe Company and Buyer shall mutually agree (“Mailing Date”) to each holder of record of CompanyCommon Stock as of five (5) business days prior to the Mailing Date (“Election Form Record Date”).Buyer shall make available one or more Election Forms as may be reasonably requested by all personswho become holders (or beneficial owners) of Company Common Stock after the Election Form RecordDate and prior to the Election Deadline, and the Company shall provide to the Exchange Agent allinformation reasonably necessary for it to perform its obligations as specified herein. EachElection Form shall permit the holder (or the beneficial owner through appropriate and customarydocumentation and instructions) to elect (an “Election”) to receive either (i) Buyer Common Stock(a “Stock Election”) with respect to all of such holder’s Company Common Stock, (ii) cash (a “CashElection”) with respect to all of such holder’s Company Common Stock, or (iii) Buyer Common Stockwith respect to a specified number of shares of such holder’s Company Common Stock (a “CombinationStock Election”) and cash with respect to the remainder of such holder’s Company Common Stock (a“Combination Cash Election”), subject to the provisions contained in this Agreement. Any CompanyCommon Stock (other than Dissenting Shares) with respect to which the holder (or the beneficialowner, as the case may be) shall not have submitted to the Exchange Agent, an effective, properlycompleted Election Form received prior to the Election Deadline shall be deemed to be “UndesignatedShares” hereunder.          (b) Any Election shall have been properly made and effective only if the Exchange Agent shallhave actually received a properly completed Election Form by 5:00 p.m. California time on or beforethe thirtieth (30th) day following the Mailing Date, or such other time and date as Buyer and theCompany may mutually agree (the “Election Deadline”). An Election Form shall be deemed properlycompleted only if an Election is indicated for each share of Company Common Stock covered by suchElection Form. Any Election Form may be revoked or changed by the person submitting such ElectionForm at or prior to the Election Deadline. In the event an Election Form is revoked prior to theElection Deadline, the shares of Company Common Stock represented by such Election Form shallautomatically become Undesignated Shares unless and until a new Election is properly completed andmade with
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respect to such shares on or before the Election Deadline, and, if such revoked Election Formwas delivered to the Exchange Agent accompanied by Certificates represented by such Election Form,Buyer shall cause such Certificates to be promptly returned without charge to the person submittingthe revoked Election Form upon written request to that effect from the holder who submitted suchElection Form. Subject to the terms of this Agreement and of the Election Form, the Exchange Agentshall have reasonable discretion to determine whether any election, revocation or change has beenproperly or timely made and to disregard immaterial defects in the Election Forms, and anydecisions of Buyer and the Company required by the Exchange Agent and made in good faith indetermining such matters shall be binding and conclusive. Neither Buyer nor the Exchange Agentshall be under any obligation to notify any person of any defect in an Election Form.          (c) Buyer shall use commercially reasonable efforts to cause the Exchange Agent to effect theallocation among the holders of Company Common Stock of rights to receive cash or Buyer CommonStock in the Merger as follows:               (i) If the conversion of all Cash Election Shares would result in an Aggregate Stock Value notless than forty-five percent (45%) of the Aggregate Deal Value:                    (A) and if such conversion would not result in the Aggregate Cash Value exceeding the FixedCash Amount, then:                         (1) each Stock Election Share shall be converted into the right to receive that number ofshares of Buyer Common Stock equal to the Exchange Ratio;                         (2) each Undesignated Share shall be converted into the right to receive that number of sharesof Buyer Common Stock equal to the Exchange Ratio; and                         (3) each Cash Election Share shall be converted into the right to receive cash in an amountequal to the Per Share Cash Consideration;                    (B) and if such conversion would result in the Aggregate Cash Value exceeding the Fixed CashAmount, then:                         (1) each Stock Election Share shall be converted into the right to receive that number ofshares of Buyer Common Stock equal to the Exchange Ratio;                         (2) each Undesignated Share shall be converted into the right to receive that number of sharesof Buyer Common Stock equal to the Exchange Ratio; and                         (3) a cash proration factor (the “Fixed Cash Proration Factor”) shall be determined bydividing (a) the quotient of (i) the Fixed Cash Value, divided by (ii) the Per Share CashConsideration, by (b) the Aggregate Cash Election Share Number. Each holder of Cash ElectionShares shall be entitled to:                              (x) an amount of cash equal to the product of (a) the number of such holder’s Cash ElectionShares, multiplied by (b) the Per Share Cash Consideration, multiplied by (c) the Fixed CashProration Factor; and
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                              (y) that number of shares of Buyer Common Stock equal to the product of (a) the number of suchholder’s Cash Election Shares, multiplied by (b) the Exchange Ratio, multiplied by (c) thedifference of (i) one minus (ii) the Fixed Cash Proration Factor;                    provided, however, that a further allocation of shares of Buyer Common Stock in lieu of thePer Share Cash Consideration upon conversion of Cash Election Shares may be made on a pro ratabasis if and to the extent necessary to ensure that, after the payment of cash for fractionalshares in accordance with Section 1.5(b) hereof and for Dissenting Shares in accordance withSection 2.2(c)(v), the Aggregate Stock Value is not less than forty-five percent (45%) of theAggregate Deal Value.               (ii) If the conversion of all Cash Election Shares would result in an Aggregate Stock Valueless than forty-five percent (45%) of the Aggregate Deal Value, then, to the extent necessary sothat the Aggregate Stock Value is not less than forty-five percent (45%) of the Aggregate DealValue, the Exchange Agent shall make the following allocations and adjustments in the followingorder:                    (A) each Stock Election Share shall be converted into the right to receive that number ofshares of Buyer Common Stock equal to the Exchange Ratio;                    (B) each Undesignated Share shall be converted into the right to receive that number of sharesof Buyer Common Stock equal to the Exchange Ratio; and                    (C) a cash proration factor (the “Cash Proration Factor”) shall be determined by dividing (I)the quotient of (a) the product of (i) the Aggregate Deal Value, multiplied by (ii) 0.55, dividedby (b) the Per Share Cash Consideration, by (II) the Aggregate Cash Election Share Number. Eachholder of Cash Election Shares shall be entitled to:                         (1) an amount of cash equal to the product of (a) the number of such holder’s Cash ElectionShares, multiplied by (b) the Per Share Cash Consideration, multiplied by (c) the Cash ProrationFactor; and                         (2) that number of shares of Buyer Common Stock equal to the product of (a) the number of suchholder’s Cash Election Shares, multiplied by (b) the Exchange Ratio, multiplied by (c) thedifference of (i) one minus (ii) the Cash Proration Factor;                    provided, however, that a further allocation of shares of Buyer Common Stock in lieu of thePer Share Cash Consideration upon conversion of Cash Election Shares may be made on a pro ratabasis if and to the extent necessary to ensure that, after the payment of cash for fractionalshares in accordance with Section 1.5(b) hereof and for Dissenting Shares in accordance withSection 2.2(c)(v), the Aggregate Stock Value is not less than forty-five percent (45%) of theAggregate Deal Value.               (iii) Notwithstanding any other provision of this Agreement (other than Section 2.2(c)(iv)hereof):
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                    (A) if the Average Closing Price is eighty percent (80%) or greater, but less than eighty-fivepercent (85%), of the Agreement Price, the Exchange Ratio shall be adjusted to the product of (I)1.108, and (II) a fraction, the numerator of which is the product of (a) the Agreement Price, and(b) 0.85, and the denominator of which is the Average Closing Price; and                    (B) if the Average Closing Price is greater than one hundred fifteen percent (115%), but notgreater than one hundred twenty percent (120%), of the Agreement Price, the Exchange Ratio shall beadjusted to the product of (I) 1.108, and (II) a fraction, the numerator of which is the product of(a) the Agreement Price, and (b) 1.15, and the denominator of which is the Average Closing Price.               (iv) Notwithstanding any other provision of this Agreement, after application of theallocation rules set forth in the preceding subsections of this Section 2.2(c), Buyer shall beauthorized to reallocate cash and shares of Buyer Common Stock among the holders of the CompanyCommon Stock in good faith, and thus to vary the number of shares of Buyer Common Stock to beissued in the Merger, if and to the extent necessary, as may be reasonably determined jointly byBuyer and the Company, to secure the tax opinions described in Section 8.2(g) and Section 8.3(e)below.               (v) Notwithstanding any other provision of this Agreement (other than Section 2.2(c)(iv)hereof), all shares of Company Common Stock which are outstanding immediately prior to theEffective Time and that have ceased to be Dissenting Shares shall be deemed “Undesignated Shares.”          (d) The calculations required by Section 2.2(c) above shall be prepared by Buyer prior to theEffective Time and shall be set forth in a certificate executed by the Chief Financial Officer ofBuyer and furnished to the Company at least two (2) business days prior to the Effective Timeshowing the manner of calculation in reasonable detail. Any calculation of a portion of a share ofBuyer Common Stock shall be rounded to the nearest ten-thousandth of a share, and any cash paymentshall be rounded to the nearest cent.          (e) No dividends or other distributions of any kind which are declared payable to holders ofrecord of Buyer Common Stock after the Effective Time will be paid to persons entitled to receivesuch certificates representing Buyer Common Stock until such persons surrender their Certificates.Upon surrender of such Certificates, the holders thereof shall be paid, without interest, anydividends or other distributions with respect to shares of Buyer Common Stock as to which therecord date and payment date occurred after the Effective Time and on or before the date ofsurrender.          (f) All dividends or distributions, and any cash to be paid pursuant to Section 1.5(b) hereofin lieu of fractional shares, if held by the Exchange Agent for payment or delivery to the holdersof unsurrendered Certificates and unclaimed at the end of one year from the date of the EffectiveTime, shall (together with any interest earned thereon) at such time be paid or redelivered by theExchange Agent to Buyer, and after such time any holder of a Certificate who has not surrenderedsuch Certificate to the Exchange Agent shall, subject to applicable law, only
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have the rights of a general creditor of Buyer for payment or delivery by Buyer of suchdividends or distributions or cash, as the case may be.Buyer, UCB, the Company or the Exchange Agent shall be entitled to deduct and withhold from theMerger Consideration otherwise payable pursuant to this Agreement such cash amounts as Buyer, UCB,the Company or the Exchange Agent are required to deduct and withhold under the Code, or anyprovision of state, local or foreign law with respect to the making of such payment. To the extentthe amounts are so withheld by Buyer, UCB, the Company or the Exchange Agent, such withheld amountsshall be treated for all purposes of this Agreement as having been paid to the holder of shares ofthe Company Common Stock in respect of whom such deduction and withholding was made by Buyer, UCB,the Company or the Exchange Agent.     2.3 Further Transfers of Company Common Stock. From and after the Effective Time, thestock transfer books of the Company shall be closed and no transfer of shares of Company CommonStock theretofore outstanding shall thereafter be made. If, after the Effective Time, Certificatesrepresenting such shares are presented for transfer to the Surviving Corporation or the ExchangeAgent, they shall be cancelled and exchanged for the Merger Consideration as provided in thisArticle II.     2.4 Dissenting Shares. Any Dissenting Shares of Company Common Stock held by personswho have perfected their rights with respect to such Dissenting Shares under Section 86 *et seq*.shall not be converted pursuant to this Agreement, but the holders thereof shall be entitled tosuch rights as are granted them by Section 86 *et seq*. Each holder of Dissenting Shares who isentitled to payment for such holder’s shares of Company Common Stock pursuant to Section 86 *et seq*.shall only receive payment from Buyer in an amount as determined pursuant to the procedures setforth in Section 86 *et seq*.     2.5 Alternative Method. Notwithstanding any provision of this Agreement to thecontrary, after consultation with the Company, upon written notice to the Company, Buyer may, atany time prior to the Effective Time, to the extent permitted by law, change the method ofeffecting the Merger or the making of Merger Consideration available to the Company’s shareholdersif, and to the extent necessary to secure the tax opinions described in Section 8.2(g) and Section8.3(e) below; provided, however, that no such change shall (i) alter or change the amount or kindof Merger Consideration, (ii) materially delay or impede the consummation of the Merger, or (iii)adversely affect the tax treatment of Company shareholders as a result of receiving Buyer CommonStock or the status of the Merger as a “reorganization” within the meaning of section 368(a) of theCode.**ARTICLE III****DISCLOSURE SCHEDULES; REPRESENTATIONS**