<PAGE>

                                                                     EXHIBIT 4.1

                          CERTIFICATE OF DETERMINATION
                                       OF
           SERIES A NON-VOTING CONVERTIBLE REDEEMABLE PREFERRED STOCK
                                       OF
                            MISSION COMMUNITY BANCORP

                            a California corporation


         The undersigned, Anita M. Robinson and Roxanne M. Carr, hereby certify
that:

         A. They are the duly elected and acting President and Secretary,
respectively, of Mission Community Bancorp, a California corporation (the
"Company").

         B. The authorized number of shares of preferred stock is 1,000,000,
none of which has been issued. The number of shares of Series A Non-Voting
Convertible Redeemable Preferred Stock is 100,000, none of which has been
issued.

         C. Pursuant to authority given by said Company's Articles of
Incorporation, the Board of Directors of the Company duly has adopted the
following recitals and resolutions:

         "WHEREAS, the Articles of Incorporation of the Company authorize a
         class of preferred stock comprising 1,000,000 shares issuable from time
         to time in one or more series; and

         WHEREAS, the Board of Directors of the Company is authorized to fix or
         alter the rights, preferences, privileges and restrictions granted to
         or imposed upon any wholly unissued series of preferred stock including
         but not limited to the dividends rights, dividend rates, conversion
         rights, voting rights, and the liquidation preferences, and the number
         of shares constituting any such series and the designation thereof, or
         any of them; and

         WHEREAS, the Company heretofore has not issued or designated any series
         of preferred stock, and it is the desire of the Board of Directors of
         the Company, pursuant to its authority as aforesaid, to fix the rights,
         preferences, privileges and restrictions and other matters relating to
         Series A Non-Voting Convertible Redeemable Preferred Stock and the
         number of shares constituting such series;

         NOW, THEREFORE, BE IT HEREBY RESOLVED, that the Board of Directors of
         the Company hereby fixes and determines the designation of, the number
         of shares constituting, and the rights, preferences, privileges and
         restrictions relating to, the initial series of preferred stock as
         follows:

                  1. DESIGNATION AND NUMBER OF SHARES. This series of Preferred
Stock shall be


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<PAGE>

designated "Series A Non-Voting Convertible Redeemable Preferred Stock" (the
"Series A Preferred Stock"), and the number of shares which shall constitute
such series shall be 100,000. The stated value of the Series A Preferred Stock
shall be $5.00 per share.

                  2. VOTING RIGHTS. The holders of Series A Preferred Stock
shall not, by virtue of their ownership thereof, be entitled to vote on any
matter, except as otherwise required by the California Corporations Code.

                  3. REDEMPTION.

                  (a) Subject to the receipt of any required regulatory
approval, the Series A Preferred Stock shall be automatically redeemable, in
whole or in part, at any time upon the request of the holder of the Series A
Preferred Stock, in cash at the price of $5.00 per share, without further action
on the part of the Company, upon and after a finding by the Community
Development Financial Institutions Fund ("CDFI"), or its successor agency or
entity, that the Company is in default under any Community Development Financial
Institutions Program Assistance Agreement for Equity Investments in Regulated
Institutions, or any successor agreement, to which the Company is a party or by
which it is bound.

                  (b) No sinking fund will be established for the redemption of
shares of the Series A Preferred Stock.

                  4. DIVIDENDS.

                  (a) No dividend (except a dividend payable solely in Common
Stock of the Company) shall be paid to the holders of Common Stock at any time
unless concurrently dividends are paid or declared and set apart for payment
with respect to all outstanding shares of the Series A Preferred Stock in an
amount for each share of Series A Preferred Stock equal to 50% of the amount of
the dividend that would be payable on the shares of Common Stock. The Series A
Preferred Stock shall not be entitled to any fixed rate of return.

                  (b) No dividend shall be paid or declared and set apart for
payment on the Series A Preferred Stock unless full dividends (which shall be
cumulative with respect to shares of Prior Stock [as hereinafter defined] which
by their terms bear cumulative dividends from the date from and after which
dividends thereon are cumulative) have been or contemporaneously are paid or
declared and set apart for payment on all Prior Stock. No dividend shall be paid
or declared and set apart for payment on the Series A Preferred Stock to the
exclusion of any Parity Stock (as hereinafter defined).

                  5. LIQUIDATION.

                  (a) In the event of any liquidation, dissolution or winding up
of the Company, either voluntary or involuntary, the holders of the Series A
Preferred Stock shall not be entitled to


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<PAGE>

receive, from any of the assets or surplus funds of the Company legally
available for distribution, any payment or distribution until payment in full of
all preferential amounts provided for in Prior Stock of the Company.

                  (b) In the event of any liquidation, dissolution or winding up
of the Company, either voluntary or involuntary, after all creditors of the
Company shall have been paid in full and holders of Prior Stock shall have
received payment in full of the preferential amounts to which they are entitled,
the holders of the Series A Preferred Stock shall be entitled to receive, prior
and in preference to any distribution of any of the assets or surplus funds of
the Company legally available for distribution to the holders of the Common
Stock or any Junior Stock, the amount of $5.00 per share (as adjusted for any
stock dividends, combinations or splits with respect to such shares) plus all
declared but unpaid dividends on such shares. If the assets and funds available
for distribution to the holders of the Series A Preferred Stock and any Parity
Stock shall be insufficient to pay the stated preferential amounts in full, then
the entire assets and funds of the Company legally available for distribution
shall be distributed to the holders of the Series A Preferred Stock and the
Parity Stock in proportion to the preferential amount each such holders is
otherwise entitled to receive.

                  (c) After payment in full of the preferential amounts to the
holders of the Series A Preferred Stock, any Prior Stock, any Parity Stock and
any Junior Stock, the holders of the Common Stock shall be entitled to receive
the amount of $10.00 per share (as adjusted for any stock dividends, combination
or splits with respect to such shares), plus all declared but unpaid dividends
on such shares. If the assets and funds available for distribution to the
holders of the Common Stock shall be insufficient to pay the stated preferential
amount in full, then the entire remaining assets and funds of the Company
legally available for distribution shall be distributed ratably to the holders
of the Common Stock.

                  (d) After payment in full of the preferential amounts has made
to the holders of the Series A Preferred Stock, any Prior Stock, any Parity
Stock, any Junior Stock and the Common Stock as set forth above, all remaining
assets of the Company legally available for distribution shall be distributed
ratably among holders of the Common Stock and the Series A Preferred Stock and
any Parity Stock in proportion to the number of shares of Common Stock held by
them and issuable upon conversion of the Series A Stock and Parity Stock held by
them.

                  (e) For purposes of this Paragraph 5, a liquidation,
dissolution or winding up of the Company shall be deemed to include the
Company's sale of all or substantially all of its assets. Neither the purchase
nor redemption by the Company of shares of any class of stock in any manner
permitted by the articles of incorporation or California law, nor the merger or
consolidation of the Company with or into any other corporation or corporations,
shall be deemed to be a liquidation, dissolution or winding up of the Company
for the purposes of this Paragraph 5.


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<PAGE>

                  6. CONVERSION.

         The holders of the Series A Preferred Stock shall have conversion
rights as follows (the "Conversion Rights"):

                  (a) RIGHT TO CONVERT. Each share of Series A Preferred Stock
shall be convertible, at the option of the holder thereof, at any time at or
after the sale, transfer or other disposition (whether or not for value) by CDFI
(other than to an affiliate of CDFI) of such shares of Series A Preferred Stock,
at the office of the Company or any transfer agent for such stock into such
number of fully paid and nonassessable shares of Common Stock as is determined
by dividing $5.00 by the then effective Conversion Price. The initial Series A
Preferred Stock Conversion Price is $10.00. The Conversion Price is subject to
adjustment as provided in this Paragraph 6.

                  (b) MECHANICS OF CONVERSION. No fractional shares of Common
Stock shall be issued upon conversion of the Series A Preferred Stock. In lieu
of any fractional shares to which the holder would otherwise be entitled, the
Company shall pay cash equal to such fraction multiplied by the then effective
Conversion Price. Conversion of the Series A Preferred Stock at the option of
the holder shall be effected by delivery, to the office of the Company or to any
transfer agent for such shares, of duly endorsed certificates for the shares
being converted and of written notice to the Company that the holder elects to
convert such shares. Conversion shall be deemed to occur immediately prior to
the close of business on the date the shares and notice are delivered. Holders
entitled to receive Common Stock upon conversion of Series A Preferred Stock
shall be treated for all purposes as the record holders of such shares of Common
Stock on the date conversion is deemed to occur. The Company shall not be
obligated to issue certificates evidencing shares of Common Stock issuable upon
conversion of Series A Preferred Stock unless the certificates evidencing such
shares being converted are either delivered to the Company or its transfer agent
as provided above, or the holder notifies the Company or its transfer agent that
such certificates have been lost, stolen or destroyed and executes an agreement,
and at the Company's election provides a surety bond or other security,
satisfactory to the Company to indemnify the Company from any loss incurred by
it in connection with such certificates. The Company shall, as soon as
practicable after such delivery, or such agreement and indemnification in the
case of a lost certificate, issue and deliver at such office to the holder of
the Series A Preferred Stock being converted, a certificate or certificates for
the number of shares of Common Stock to which the holder is entitled and a check
payable to the holder for any cash due with respect to fractional shares.

                  (c) ADJUSTMENTS OF CONVERSION PRICE FOR CERTAIN DILUTING
ISSUES.

                  (i) SPECIAL DEFINITIONS. For purposes of this Paragraph 6, the
following definitions shall apply:


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<PAGE>

                  (1) "OPTIONS" shall mean rights, options or warrants to
subscribe for, purchase or otherwise acquire Common Stock or Convertible
Securities.

                  (2) "ORIGINAL ISSUE DATE" shall mean the date on which the
first share of Series A Preferred Stock was issued.

                  (3) "CONVERTIBLE SECURITIES" shall mean instruments of
indebtedness or securities convertible into or exchangeable for Common Stock.

                  (4) ADDITIONAL SHARES OF COMMON STOCK shall mean all shares of
Common Stock issued (or pursuant to Paragraph 6(c)(iii), deemed to be issued) by
the Company after the Original Issue Date, other than Common Stock issued or
issuable:

                           (A) upon conversion of Series A Preferred Stock;

                           (B) to officers, directors, employees of and service
                           providers to the Company pursuant to plans and
                           arrangements approved by the Board of Directors;

                           (C) as a dividend or other distribution on the Series
                           A Preferred Stock or any event for which adjustment
                           is made pursuant to Paragraph 6(d), (e) or (f);

                           (D) upon the exercise or conversion of outstanding
                           options or warrants; or

                           (E) by way of dividend or other distributions on
                           securities referred to in these clauses (A), (B),
                           (C), (D) and (E).

                  (ii) NO ADJUSTMENT OF CONVERSION PRICE. No adjustment in the
Conversion Price shall be made in respect of the issuance of Additional Shares
of Common Stock unless the consideration per share for an Additional Share of
Common Stock issued or deemed to be issued by the Company is less than the
Conversion Price in effect immediately prior to such issue.

                  (iii) DEEMED ISSUE OF ADDITIONAL SHARES OF COMMON STOCK. If
the Company at any time after the Original Issue Date shall issue any Options or
Convertible Securities or shall fix a record date for the determination of any
holders of any class of securities entitled to receive any such Options or
Convertible Securities, then the maximum number of shares (as set forth in the
instrument relating thereto without regard to any provisions contained therein
for a subsequent adjustment of such number) of Common Stock issuable upon the
exercise of such


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<PAGE>

Options or, in the case of Convertible Securities and Options for Convertible
Securities, the conversion or exchange of such Convertible Securities, shall be
deemed to be Additional Shares of Common Stock issued as of the time of such
issue or, in case such a record date shall have been fixed, as of the close of
business on such record date, provided that in any such case in which Additional
Shares of Common Stock are deemed to be issued:

                           (A) no further adjustment in the Conversion Price
                           shall be made upon the subsequent issue of
                           Convertible Securities or shares of Common Stock
                           issued upon the exercise of such Options or
                           conversion or exchange of such Convertible
                           Securities;

                           (B) if such Options or Convertible Securities by
                           their terms provide, with the passage of time or
                           otherwise, for any increase or decrease in the
                           consideration payable to the Company, or increase or
                           decrease in the number of shares of Common Stock
                           issuable, upon the exercise, conversion or exchange
                           thereof, the Conversion Price computed upon the
                           original issue thereof (or upon the occurrence of a
                           record date with respect thereto), and any subsequent
                           adjustments based thereon, shall, upon any such
                           increase or decrease, becoming effective, be
                           recomputed to reflect such increase or decrease
                           insofar as it affects such Options or the rights of
                           conversion or exchange under such Convertible
                           Securities;

                           (C) upon the expiration of any such Options or any
                           rights of conversion or exchange under such
                           Convertible Securities which shall not have been
                           exercised, the Conversion Price computed upon the
                           original issue thereof (or upon the occurrence of a
                           record date with respect thereto), and any subsequent
                           adjustments based thereon, shall, upon such
                           expiration, be recomputed as if:

                                    (i) in the case of Convertible Securities or
                                    Options for Common Stock, the only
                                    additional shares of Common Stock issued
                                    were shares of Common Stock, if any,
                                    actually issued upon the exercise of such
                                    Options or the conversion or exchange of
                                    such Convertible Securities, and the
                                    consideration received therefor was the
                                    consideration actually received by the
                                    Company for the issue of all such Options,
                                    whether or not exercised, plus the
                                    consideration actually received by the
                                    Company upon such exercise, or for the issue
                                    of all such Convertible Securities which
                                    were actually converted or exchanged, plus
                                    the additional consideration, if any,
                                    actually received by the Company upon such
                                    conversion, or


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<PAGE>

                                    exchange, and

                                    (ii) in the case of Options for Convertible
                                    Securities, only the Convertible Securities,
                                    if any, actually issued upon the exercise
                                    thereof were issued at the time of issue of
                                    such Options and the consideration received
                                    by the Company for the Additional Shares of
                                    Common Stock deemed to have been then issued
                                    was the consideration actually received by
                                    the Company for the issue of all such
                                    Options, whether or not exercised, plus the
                                    consideration deemed to have been received
                                    by the Company upon the issue of the
                                    Convertible Securities with respect to which
                                    such Options were actually exercised;

                  (D) no readjustment pursuant to clause (B) or (C) above shall
                  have the effect of increasing the Conversion Price to an
                  amount which exceeds the lower of (i) the Conversion Price on
                  the original adjustment date, or (ii) the Conversion Price
                  that would have resulted from any issuance of Additional
                  Shares of Common Stock between the original adjustment date
                  and such readjustment date, and no readjustment shall affect
                  Common Stock issued on conversion of Series A Preferred Stock
                  prior to such readjustment; and

                  (E) in the case of any Options which expire by their terms not
                  more than 90 days after the date of issue thereof, no
                  adjustment of the Conversion Price shall be made until the
                  expiration or exercise of all such Options.

                  (iv) ADJUSTMENT OF CONVERSION PRICE UPON ISSUANCE OF
ADDITIONAL SHARES OF COMMON STOCK. If the Company issues Additional Shares of
Common Stock (including Additional Shares of Common Stock deemed to be issued
pursuant to Paragraph 6(c)(iii)) without consideration or for a consideration
per share less than the Conversion Price in effect immediately prior to such
issue, then and in such event, such Conversion Price shall be reduced,
concurrently with such issue, to a price equal to the Effective Price (as
defined below) of such Additional Shares of Common Stock. The "Effective Price"
of Additional Shares of Common Stock shall mean the quotient determined by
dividing the total number of Additional Shares of Common Stock issued or sold,
or under Paragraph 6(c)(iii) deemed to have been issued or sold, into the
aggregate consideration received, or under Paragraph 6(c)(iii) deemed to have
been received, by the Company for such Additional Shares of Common Stock.

                  (v) DETERMINATION OF CONSIDERATION. For purposes of this
Paragraph 6(c), the consideration received by the Company for the issue of any
Additional Shares of Common Stock shall be computed as follows:


                                       7
<PAGE>

                  (1)      CASH AND PROPERTY: Such consideration shall:

                           (A) insofar as it consists of cash, be computed at
                           the aggregate amount of cash received by the Company
                           prior to amounts paid or payable for accrued interest
                           or accrued dividends and prior to any commissions or
                           expenses paid by the Company;

                           (B) insofar as it consists of property other than
                           cash, be computed at the fair value thereof at the
                           time of such issue, as determined in good faith by
                           the Board of Directors; and

                           (C) if Additional Shares of Common Stock are issued
                           together with other shares or securities or other
                           assets of the Company for consideration which covers
                           both, be the proportion of such consideration so
                           received, computed as provided in clauses (A) and (B)
                           above, as determined in good faith by the Board of
                           Directors.

                  (2) OPTIONS AND CONVERTIBLE SECURITIES. The consideration per
share received by the Company for Additional Shams of Common Stock deemed to
have been issued pursuant to Paragraph 6(c)(iii), relating to Options and
Convertible Securities, shall be determined by dividing

                  (x) the total amount, if any, received or receivable by the
Company as consideration for the issue of such Options or Convertible
Securities, plus the minimum aggregate amount of additional consideration (as
set forth in the instruments relating thereto, without regard to any provision
contained therein for a subsequent adjustment of such consideration) payable to
the Company upon the exercise of such Option or the conversion or exchange of
such Convertible Securities, or in the case of Options for Convertible
Securities, the exercise of such Options for Convertible Securities and the
conversion or exchange of such Convertible Securities by

                  (y) the maximum number of shares of Common Stock (as set forth
in the instruments relating thereto, without regard to any provision contained
therein for a subsequent adjustment of such number) issuable upon the exercise
of such Options or the conversion or exchange of such Convertible Securities.

                  (d) ADJUSTMENTS FOR STOCK DIVIDENDS, COMBINATIONS OR SPLITS.
If the outstanding shares of Common Stock are subdivided, by stock split or
otherwise, into a greater number of shares of Common Stock, or if the Company
shall declare or pay any dividend on the Common Stock payable in shares of
Common Stock, then the Conversion Price in effect prior to


                                       8
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such event shall be proportionately decreased upon the occurrence of such event.
If the outstanding shares of Common Stock are combined or consolidated, by
reclassification, reverse stock split or otherwise, into a lesser number of
shares of Common Stock, then the Conversion Price in effect prior to such event
shall be proportionately increased upon the occurrence of such event.

                  (e) ADJUSTMENTS FOR OTHER DISTRIBUTIONS. If the Company fixes
a record date for the determination of holders of Common Stock entitled to
receive any distribution payable in securities of the Company other than shares
of Common Stock (excluding any distribution in which the Series A Preferred
Stock participates on an as-converted basis, and any distribution for which
adjustment is otherwise made pursuant to this Paragraph 6), then in each such
case provision shall be made so that the holders of Series A Preferred Stock
receive upon conversion, in addition to the Common Stock issuable upon
conversion of their shares, the property or other securities of the Company
which they would have received had their shares of Series A Preferred Stock been
converted into Common Stock immediately prior to such event and had they
thereafter retained such securities, subject to all other adjustments called for
during such period under this Paragraph 6.

                  (f) ADJUSTMENTS FOR RECLASSIFICATION, EXCHANGE AND
SUBSTITUTION. If the Common Stock is changed into the same or different number
of shares of any other class or series of stock, whether by capital
reorganization, reclassification or otherwise (other than an event treated under
Paragraph 5 as a liquidation, dissolution or winding up, and other than a stock
dividend, combination, split or other event for which adjustment is made
pursuant to Paragraph 6(d)), the Conversion Price then in effect shall,
concurrently with the effectiveness of such reorganization or reclassification,
be adjusted such that the Series A Preferred Stock shall be convertible into, in
lieu of the Common Stock which the holders would otherwise have been entitled to
receive, a number of shares of such other class or series of stock equivalent to
the number of shares of Common Stock that the holders would have been entitled
to receive upon conversion of their Series A Preferred Stock immediately prior
to such reclassification or capital reorganization.

                  (g) NO IMPAIRMENT. The Company will not, by amendment of its
Articles of Incorporation or through any reorganization, transfer of assets,
consolidation, merger, dissolution, issue or sale of securities or any other
voluntary action, avoid or seek to avoid the observance or performance of any of
the terms to be observed or performed hereunder by the Company but will at all
times in good faith assist in the carrying out of all the provisions of this
Paragraph 6 and in the taking of all such action as may be necessary or
appropriate in order to protest the Conversion Rights of the holders of the
Series A Preferred Stock against impairment.

                  (h) CERTIFICATE AS TO ADJUSTMENTS. The Company shall promptly
compute each


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Conversion Price adjustment and provide each holder of the Series A Preferred
Stock a certificate describing such adjustment and showing in detail the facts
upon which such adjustment is based. If requested in writing by any holder of
Series A Preferred Stock, the Company shall provide such holder a certificate
describing any Conversion Price adjustments, the current Conversion Price and
the amount of Common Stock or other property issuable upon conversion.

                  (i) NOTICES OF RECORD DATE. If the Company shall propose at
any time:

                  (i) to declare any dividend or distribution upon its Common
Stock other than a distribution payable solely in Common Stock;

                  (ii) to offer for subscription pro rata to the holders of any
class or series of its stock any additional shares of stock of any class or
series or other rights;

                  (iii) to effect any reclassification or recapitalization of
its Common Stock; or

                  (iv) to merge or consolidate with or into any other
corporation, or sell, lease or convey all or substantially all its property or
business, or to liquidate, dissolve or wind up;

then, in connection with each such event, the Company shall send to the holders
of the Series A Preferred Stock:

                  (1) at least 20 days' prior written notice of the date on
which a record shall be taken for such dividend, distribution or subscription
rights (and specifying the date on which the holders of Common Stock shall be
entitled thereto) or for determining rights to vote in respect of the matters
referred to in (iii) and (iv) above; and

                  (2) in the case of the matters referred to in (iii) and (iv)
above, at least 20 days' prior written notice of the date when the same shall
take place (and specifying the date on which the holders of Common Stock shall
be entitled to exchange their Common Stock for securities or other property
deliverable upon the occurrence of such event).

         Each such written notice shall be delivered personally or given by
first class mail, postage prepaid, addressed to the holders of Series A
Preferred Stock at the address for each such holder as shown on the books of
this Company.

                  7. NO REISSUANCE. No shares of Series A Preferred Stock
acquired by the Company by reason of redemption, purchase or otherwise shall be
reissued, and all such shares shall be canceled, retired and eliminated from the
shares which the Company shall be authorized


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<PAGE>

to issue.

                  8. DEFINITIONS. As used in this Resolution, the following
terms have the following meanings:

                  (a) The term "Common Stock" shall mean the class of stock
designated as the common stock of the Company at the date of the adoption of
this Resolution or any other class of stock resulting from successive changes or
reclassifications of the common stock.

                  (b) The term "Parity Stock" means (y) as used in Paragraph 4,
above, any class or series of stock of the Company hereafter authorized or
issued ranking on a parity with the Series A Preferred Stock in the payment of
dividends, and (z) as used in Paragraph 5, above, any class or series of stock
of the Company hereafter authorized or issued ranking on a parity with the
Series A Preferred Stock in the distribution of assets on any liquidation,
dissolution or winding up of the Company.

                  (c) The term "Prior Stock" means (y) as used in Paragraph 4,
above, any class or series of stock of the Company hereafter authorized or
issued which has preference or priority in the payment of dividends over the
Series A Preferred Stock, and (z) as used in Paragraph 5, above, any class or
series of stock of the Company hereafter authorized or issued which has
preference or priority over the Series A Preferred Stock in the distribution of
assets on any liquidation, dissolution or winding up of the Company.

                  (d) The term "Junior Stock" means, as used in Paragraph 5,
above, any class or series of stock of the Company (other than the Common Stock)
hereafter authorized or issued over which the Series A Preferred Stock has
preference or priority in the distribution of assets on any liquidation,
dissolution or winding up of the Company.

         RESOLVED FURTHER, that the President and the Secretary are hereby
         authorized and directed to execute and file a Certificate of
         Determination in accordance with the foregoing resolutions and
         provisions of California law."

         IN WITNESS WHEREOF, the undersigned have executed this certificate this
12th day of December, 2000.


                                              -----------------------------
                                              Anita M. Robinson, President


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<PAGE>

                                              -----------------------------
                                              Roxanne M. Carr, Secretary

         The undersigned declare under penalty of perjury that the matters set
forth in the foregoing Certificate of Determination are true and correct of
their own knowledge.

         Executed at San Luis Obispo, California on December 12, 2000.


                                              -----------------------------
                                              Anita M. Robinson


                                              -----------------------------
                                              Roxanne M. Carr

                                       12