TABLE OF CONTENTS

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ARTICLE I
THE MERGER
1.1		Effective Time of the Merger			1
1.2		Closing			1
1.3		Effects of the Merger			2
1.4		Absence of Control			2
1.5		Further Assurances			2
1.6		The Bank Merger			2
1.7		Tax Consequences			3
ARTICLE II
EFFECT OF THE MERGER ON THE CAPITAL STOCK OF COMPANY AND SUB; EXCHANGE OF CERTIFICATES
2.1		Effect of Merger on Sub Stock			3
2.2		Conversion of Company Shares in the Merger			3
2.3		No Further Ownership Rights in Company Common Stock			3
2.4		Fractional Shares			4
2.5		Surrender of Shares of Company Common Stock			4
2.6		Appraisal Rights			4
2.7		Shareholder Approval			5
ARTICLE III
REPRESENTATIONS AND WARRANTIES
3.1		Representations and Warranties of Company			5
		(a) Organization, Standing and Power			5
		(b) Capital Structure; Ownership of Company Common Stock			7
		(c) Authority; No Violation			8
		(d) Financial Statements			9
		(e) Company Information Supplied			10
		(f) Compliance with Applicable Laws			10
		(g) Litigation			11
		(h) Taxes			11

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		(i) Certain Agreements			12
		(j) Benefit Plans			13
		(k) Subsidiaries			15
		(l) Agreements with Bank or Other Regulators			15
		(m) Absence of Certain Changes or Events			16
		(n) Undisclosed Liabilities			16
		(o) Governmental Reports			17
		(p) Environmental Liability			17
		(q) Properties			19
		(r) Brokers or Finders			19
		(s) Intellectual Property			20
		(t) Insurance			20
		(u) Loans and Other Assets			20
		(v) Labor Matters			21
		(w) Internal Controls and Records			21
		(x) Fees from Employee Plans			22
3.2		Representations and Warranties of Commerce			22
		(a) Organization and Authority.			22
		(b) Valid and Binding Agreement; No Violation			22
		(c) Capital Stock of Commerce			23
		(d) Financial Statements			23
		(e) SEC Reports			23
		(f) Status of Commerce Common Stock to be Issued			24
		(g) Governmental Regulation			24
		(h) Litigation			24
		(i) Taxes			24
		(j) Defaults			24
		(k) Information Supplied			24
		(l) Welfare Benefit Plan			25
ARTICLE IV
COVENANTS RELATING TO CONDUCT OF BUSINESS
4.1		Covenants of Company			25

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4.2		Cooperation With Commerce			28
4.3		Covenants of Commerce and Sub			29
		(a) Regulatory Approvals			29
		(b) Information			30
		(c) Tax-Free Reorganization Treatment			30
		(d) Employee Benefits			30
ARTICLE V
ADDITIONAL AGREEMENTS
5.1		Regulatory Matters			30
		(a) Registration Statement and Proxy Statement			30
		(b) State Securities Laws			31
		(c) Affiliates			31
		(d) Indemnification			31
		(e) Governmental Entity Communications			31
5.2		Shareholders Meetings			31
5.3		Acquisition Proposals			32
5.4		Legal Conditions			33
5.5		Plan Termination			33
5.6		Additional Agreements			33
5.7		Fees and Expenses			33
5.8		Cooperation			34
5.9		Advice of Changes			34
5.10		Dissenters Rights			34
5.11		Indemnification; Directors and Officers Insurance			34
5.12		Certain Financial Statement Adjustments			35
ARTICLE VI
CONDITIONS PRECEDENT
6.1		Conditions to Each Partys Obligation			35
		(a) Shareholder Approval			35
		(b) Other Approvals			35
		(c) No Injunctions or Restraints			35
		(d) Registration Statement			36

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6.2		Conditions to Obligations of Commerce and Sub			36
		(a) Representations and Warranties			36
		(b) Performance of Obligations			36
		(c) Corporate Action			36
		(d) Material Adverse Effect			36
		(e) Closing Documents			36
		(f) Financial Measures			36
		(g) Sales of Shares			37
		(h) Tax Representations			37
		(i) Dissenting Shareholders			37
		(j) Tax Opinion			37
		(k) Cancellation of Unexercised Options			37
		(l) Opinion of Counsel			37
		(m) Non-Competition Agreements			37
		(n) Termination of Fiserv Contract			37
		(o) Loan Portfolio			37
6.3		Conditions to Obligations of Company			38
		(a) Representations and Warranties			38
		(b) Performance of Obligations			38
		(c) Corporate Action			38
		(d) Tax Opinion			38
		(e) Material Adverse Effect			38
		(f) Closing Documents			38
		(g) Opinion of Counsel			38
ARTICLE VII
TERMINATION AND AMENDMENT
7.1		Termination			39
7.2		Effect of Termination			40
7.3		Amendment			41
7.4		Extension; Waiver			41
7.5		Termination Fee			41

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ARTICLE VIII
GENERAL PROVISIONS
8.1		Survival of Representations, Warranties and Covenants			42
8.2		Notices			42
8.3		Interpretation			43
8.4		Counterparts			43
8.5		Entire Agreement; No Third Party Beneficiaries; Rights of Ownership			43
8.6		Governing Law			44
8.7		Severability			44
8.8		Assignment			44
8.9		Publicity			44

List of Schedules:

Schedule 3.1(a)

Schedule 3.1(b)(iii)

Schedule 3.1(c)(ii)

Schedule 3.1(g)

Schedule 3.1(h)

Schedule 3.1(i)

Schedule 3.1(j)

Schedule 3.1(k)

Schedule 3.1(l)

Schedule 3.1(m)

Schedule 3.1(n)

Schedule 3.1(o)

Schedule 3.1(p)

Schedule 3.1(q)

Schedule 3.1(s)

Schedule 3.1(u)

Schedule 3.1(w)

Schedule 4.1

Schedule 6.2(o)

INDEX OF DEFINED TERMS

TERM		PAGE		SECTION
Acquisition Proposal		32, 5.3
Affiliate		6, 3.1(a)(vi)
Agreement		1, Intro Paragraph
ASTM		18, 3.1(p)(3)
Bank		3, 1.6
Bank Common Stock		7, 3.1(b)(ii)
Bank Merger		3, 1.6
Bank Regulators		10, 3.1(f)
BHC Act		5, 3.1(a)
Business Day		1, 1.2
Closing		1, 1.2
Closing Date		1, 1.2
Code		14, 3.1(j)
Collars		3, 2.2
Commerce		1, Intro Paragraph
Commerce Common Stock		3, 2.2
Commerce Stock Price		3, 2.2
Company		1, Intro Paragraph
Company Common Stock		3, 2.2
Company Consolidated Financial Statements		9, 3.1(d)
Company Disclosure Schedule		7, 3.1(b)(iii)
Company Dissenting Shares		4, 2.6
Company Intellectual Property		20, 3.1(s)
Company Interim Financial Statements		9, 3.1(d)
Company Options		7, 3.1(b)(i)
Company Per Share Value		3, 2.2
Company Permits		10, 3.1(f)
Company Shareholder Approval		8, 3.1(c)
Company Shareholders Meeting		10, 3.1(e)
Company Stock Option Plan		7, 3.1(b)(i)
Confidentiality Agreement		29, 4.2(a)
Consents		35, 6.1(b)
Doubtful		20, 3.1(u)(i)
DPC Shares		8, 3.1(b)(v)
Effective Time		1, 1.1
Employee Plans		13, 3.1(j)
Employees		13, 3.1(j)
Environmental Audit		18, 3.1(p)(3)
Environmental Law		19, 3.1(p)(4)
Environmental Liability		18, 3.1(p)(3)
ERISA		13, 3.1(j)
Exchange Agent		4, 2.5

TERM		PAGE		SECTION
FDIC		5, 3.1(a)
Federal Reserve		9, 3.1(c)(iii)
GAAP		10, 3.1(d)
Governmental Entity		9, 3.1(c)(iii)
Hazardous Substances		19, 3.1(p)(4)
Indemnified Party		34, 5.11(a)
Injunction		35, 6.1(c)
KGCC		1, 1.1
knowledge		6, 3.1(a)(v)
Litigation		11, 3.1(g)
Loss		20, 3.1(u)(i)
material		6, 3.1(a)(ii)
Material Adverse Effect		6, 3.1(a)(iii)
Maximum Premium Amount		34, 5.11(b)
Merger		1, Recitals
New Credit		28, 4.1(s)
OAEM		28, 4.1(s)
OGCA		1, 1.1
OREO		21, 3.1(u)(i)
Other Loans Especially Mentioned		20, 3.1(u)(i)
person		7, 3.1(a)(vii)
Preferred Stock		23, 3.2(c)
Properties		18, 3.1(p)(3)
Proxy Statement		30, 5.1(a)
Real Property		19, 3.1(p)(4)
Registration Statement		30, 5.1(a)
Requested Adjustments		35, 5.12
Requisite Regulatory Approvals		35, 6.1(b)
SEC		9, 3.1(c)(iii)
SEC Fees		33, 5.7
Securities Act		10, 3.1(e)
SFAS No. 5		6, 3.1(a)(iii)
Significant Subsidiary		33, 5.3
Stock Per Share Amount		3, 2.2
Sub		1, Intro Paragraph
Subsidiary		6, 3.1(a)(i)
Substandard		20, 3.1(u)(i)
Superior Proposal		32, 5.3
Surviving Corporation		2, 1.3(c)
Tax or Taxes		11, 3.1(h)
Tax Returns		11, 3.1(h)
Termination Fee		41, 7.5(a)
to the best knowledge of		6, 3.1(a)(v)
Transaction Agreements		6, 3.1(a)(iv)
Voting Agreements		7, 3.1(b)(iii)

     THIS AGREEMENT AND PLAN OF MERGER (this Agreement) is made and entered into as of December 4, 2006 among COMMERCE BANCSHARES, INC., a Missouri corporation (Commerce), CBI-KANSAS, INC., a Kansas corporation (Sub) and SOUTH TULSA FINANCIAL CORPORATION, an Oklahoma corporation (Company).

     WHEREAS, the Executive Committee of the Board of Directors of Commerce and the Board of Directors of Sub have approved this Agreement, declared it advisable and deem it advisable and in the best interests of their respective shareholders to consummate the transactions provided for herein in which, inter alia, Commerce and Company become affiliated through the merger of Company with and into Sub (the Merger);

     WHEREAS, the Board of Directors of Company has approved this Agreement and declared it advisable and deems it advisable and in the best interests of the shareholders of Company to consummate the Merger;

     WHEREAS, the Boards of Directors of Commerce, Sub and Company have each determined that the Merger and the other transactions contemplated by this Agreement are consistent with, and will contribute to the furtherance of, their respective business strategies and goals.

     NOW, THEREFORE, in consideration of the foregoing and the respective representations, warranties, covenants and agreements set forth herein, the parties hereto agree as follows:

ARTICLE I
THE MERGER

     1.1 Effective Time of the Merger. Subject to the terms and conditions of this Agreement, on the Closing Date (as hereinafter defined), the proper officers of Company and Sub shall execute and acknowledge the appropriate certificates of merger that shall be filed with the Kansas Secretary of State and the Oklahoma Secretary of State on the first Business Day following the Closing Date, all in accordance with the Kansas General Corporation Code (KGCC) and the Oklahoma General Corporation Act (OGCA), respectively. The Merger shall become effective on the first day of the first calendar month following the Closing Date (the Effective Time).

     1.2 Closing. The closing of the Merger (the Closing) will take place at 10 a.m., Kansas City time, on a day occurring not less than two (2) and not more than four (4) Business Days before the Effective Time and not later than thirty (30) days after the date on which the last of any condition precedent contained herein is waived or fulfilled, as specified in a notice delivered by Commerce to Company not less than three (3) Business Days prior to such Closing Date or on such other date as Company, Commerce and Sub shall mutually agree (the Closing Date). The Closing shall be held at the offices of Commerce Bank, N.A., 1000 Walnut, Kansas City, Missouri or at such other location as is agreed to in writing by the parties hereto. As used in this Agreement, Business Day shall mean any day that is not a Saturday, Sunday or other day on which banks are required or authorized by law to be closed in Missouri.

     1.3 Effects of the Merger.

          (a) At the Effective Time (i) Company shall be merged with and into Sub and the separate corporate existence of Company shall cease, (ii) the Articles of Incorporation of Sub as in effect immediately prior to the Effective Time shall be the Articles of Incorporation of the Surviving Corporation, (iii) the By-laws of Sub as in effect immediately prior to the Effective Time shall be the By-laws of the Surviving Corporation, (iv) the directors of Sub at the Effective Time shall be the directors of the Surviving Corporation and (v) the officers of Sub immediately prior to the Effective Time shall be the officers of the Surviving Corporation, until the earlier of their resignation or removal or until their respective successors are duly elected and qualified, as the case may be.

          (b) Subject to Oklahoma law, at the Effective Time, (i) Sub shall possess all assets and property of every description, and every interest therein, wherever located, and the rights, privileges, immunities, powers, franchises, and authority, of a public as well as of a private nature, of Company and all obligations belonging to or due each of Company and Sub shall be vested in Sub without further act or deed; (ii) title to any real estate or any interest therein vested in Company shall not revert or in any way be impaired by reason of the Merger; (iii) all rights of creditors and all liens on any property of Company shall be preserved unimpaired; (iv) Sub shall be liable for all the obligations of Company, and any claim existing, or action or proceeding pending, by or against either of Company or Sub, may be prosecuted to judgment with the right of appeal, as if the Merger had not taken place.