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                                                                     Exhibit 4.1

                          CERTIFICATE OF DESIGNATION OF
              THE POWERS, PREFERENCES AND RELATIVE, PARTICIPATING,
            OPTIONAL AND OTHER SPECIAL RIGHTS OF PREFERRED UNITS AND
              QUALIFICATIONS, LIMITATIONS AND RESTRICTIONS THEREOF

                                       OF

                   6.5% CUMULATIVE CONVERTIBLE PREFERRED UNITS

                                       FOR

                          ATLAS PIPELINE PARTNERS, L.P



         ATLAS PIPELINE PARTNERS, L.P., a Delaware limited partnership (the
"COMPANY") pursuant to the provisions of the Delaware Revised Uniform Limited
Partnership Act and its Limited Partnership Agreement, does hereby state and
certify that pursuant to the authority expressly vested in ATLAS PIPELINE
PARTNERS GP, LLC, its general partner (the "GENERAL PARTNER"), the General
Partner duly adopted the following resolutions, which remain in full force and
effect as of the date hereof:

         RESOLVED, that each of the 6.5% Cumulative Convertible Preferred Units
rank equally in all respects and shall be subject to the following terms and
provisions:

         1. DESIGNATION. There is hereby created a series of units designated as
the "6.5% CUMULATIVE CONVERTIBLE PREFERRED UNITS." The number of units (the
"PREFERRED UNITS") shall be 40,000 and the face value of each Preferred Unit
shall be $1,000 (the "FACE VALUE").

         2. DEFINITIONS. For purposes of this Certificate of Designations, the
following terms shall have meanings ascribed to them below:

            "CALL OPTION CONDITIONS" means (i) the Company is in compliance with
the terms of the Purchase Agreement, these Designations and the Registration
Rights Agreement; (ii) either the Registrable Securities (as defined in the
Registration Rights Agreement) are (A) eligible for resale without restriction
pursuant to Rule 144(k) under the Securities Act of 1933, as amended (the
"SECURITIES ACT") or (B) are covered by an effective registration statement (the
"REGISTRATION STATEMENT") and such registration statement is not subject to any
suspension or stop orders, the prospectus contained therein is current and
deliverable and not subject to any blackout or similar circumstance; (iii) The
Registrable Securities (as defined in the Registration Rights Agreement (as
defined below)) are listed on the Principal Market; and (iv) the Company is not
subject to any bankruptcy, insolvency or similar proceeding.

            "CHANGE OF CONTROL" means the occurrence of any of the following:

            (1) the direct or indirect sale, lease, transfer, conveyance or
other disposition (other than by way of merger or consolidation), in one or a
series of related transactions, of all or substantially all of the properties or
assets of the Company and its subsidiaries taken as a whole, to any "person" (as
that term is used in Section 13(d)(3) of the Exchange Act);


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            (2) the adoption of a plan relating to the liquidation or
dissolution of the Company or the removal of the General Partner by the limited
partners of the Company;

            (3) the consummation of any transaction (including, without
limitation, any merger or consolidation) the result of which is that any
"person" or "group" (as those terms are used in Section 13(d)(3) or Section
14(d)(2) of the Exchange Act, or any successor provision), becomes the
beneficial owner, directly or indirectly, of more than 50% of the Voting Stock
of the General Partner, measured by voting power rather than number of shares;
provided that a change of control shall not be deemed to occur solely as a
result of a transfer of the general partnership interests of the Company or the
equity interests in the General Partner to a new entity in contemplation of the
initial public offering of such new entity, or as a result of any further
offering of equity interests of such new entity (or securities convertible into
such equity interests) so long as the persons or entities that beneficially own
the general partnership interests of the Company or the equity interests in the
General Partner on the Closing Date continue to hold the general partnership
interests in such new entity (or, in the case of a new entity that is not a
partnership, no other person or group beneficially owns more than 50% of the
Voting Stock of such new entity);

            (4) the Company consolidates or merges with or into another person
or any person consolidates or merges with or into the Company, in either case
under this clause (4) in one transaction or a series of related transactions in
which immediately after the consummation thereof persons beneficially owning,
directly or indirectly, Voting Stock representing in the aggregate a majority of
the total voting power of the Voting Stock of the Company immediately prior to
such consummation do not beneficially own, directly or indirectly, Voting Stock
representing a majority of the total voting power of the Voting Stock of the
Company or the surviving or transferee person; or

            (5) the first day on which a majority of the members of the Board of
Directors of the General Partner are not Continuing Directors.

            "CLOSING PRICE" shall mean $41, as such Closing Price may be
adjusted pursuant to Section 6(d) of this Certificate of Designation.

            "COMMON UNITS" shall mean the common units representing limited
partner interests of the Company.

            "CONTINUING DIRECTORS" means, as of any date of determination, any
member of the Board of Directors of the General Partner who (1) was a member of
such Board of Directors on the Closing Date or (2) was nominated for election or
elected to such Board of Directors with the approval of either (x) a majority of
the Continuing Directors who were members of such Board at the time of such
nomination or election, or (y) any "person" or "group" (as those terms are used
in Section 13(d)(3) or Section 14(d)(2) of the Exchange Act, or any successor
provision) who owns all the general partnership interests or a majority of the
equity interests of the General Partner.


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            "CONVERSION COMMENCEMENT DATE" shall mean the date immediately
following the first record date for Common Unit dividends occurring after the
one year anniversary of the issuance of the Preferred Units; provided, however,
that if a Change in Control or a Company Event (as defined below) shall have
occurred or been announced before such date, the Conversion Commencement Date
shall be the date such Change in Control Transaction or Company Event, as the
case may be, shall have occurred or been announced.

            "CONVERSION PRICE" shall mean the lesser of (a) the Closing Price or
(b) 95% of the Market Price as of the Conversion Notice Date (as defined below);
provided, however, if the Company elects to pay the Conversion Value to Holder
instead of issuing Common Units, the Conversion Price shall be the lesser of (a)
the Closing Price or (b) 100% Market Price as of the Conversion Notice Date.

            "CONVERSION VALUE" shall mean: (i) if the Closing Price is less than
the Market Price; the number of Common Units issuable for the Preferred Units
being converted or redeemed multiplied by the Market Price and (ii) if the
Closing Price is greater than or equal to the Market Price, the Liquidation
Value (as defined below) of the Preferred Units being converted or redeemed.

            "CURRENCY CONVERSION OPTION" shall mean the right of the Company to
satisfy a Conversion Notice by paying to the Holder the Conversion Value as of
the Conversion Notice Date or Mandatory Conversion Date, as appropriate, rather
than issuing Common Units to it.

            "DIVIDEND COMMENCEMENT DATE" shall mean March 13, 2007.

            "EXCHANGE ACT" shall mean the Securities Exchange Act of 1934, as
amended.

            "FIRST CALL DATE" shall mean the one year anniversary of the
Conversion Commencement Date.

            "FIRST CALL REDEMPTION PRICE" equals $48.79 per unit (as may be
adjusted pursuant to Section 6(d)).

            "HOLDER" means Sunlight Capital Partners, LLC or any of its
transferees permitted pursuant to the terms of the Purchase Agreement (as
defined below).

            "MANDATORY CONVERSION DATE" shall mean the second year anniversary
of the Conversion Commencement Date, provided however, that if the Call Option
Conditions shall not have been satisfied for the 20 Trading Days immediately
preceding such date, the Mandatory Conversion Date shall be such later date as
such conditions shall have been satisfied.

            "MARKET PRICE" shall mean the average closing price of a Common Unit
over the ten (10) consecutive Trading Days immediately preceding the date as of
which the Market Price is being determined, provided that if the Common Units
are not then listed on any market or exchange, then the Market Price shall be
the average of the closing bid prices for the Common Units on the OTC Bulletin
Board, or, if such is not available, the National Quotation Bureau, or otherwise
the average of the closing bid prices for the Common Units quoted by two
market-makers of the Common Unit, or otherwise such Market Price shall be the
fair market value of one Common Unit as reasonably determined in good faith by
the Company and the Holders of a majority of the Preferred Units.


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            "PRINCIPAL MARKET" shall mean the New York Stock Exchange or such
other principal market or exchange on which the Common Units are then listed for
trading.

            "REDEMPTION DATE" shall mean the date upon which a redemption
effected pursuant to the exercise of a Call Option or Special Call Option shall
be consummated.

            "SECOND CALL DATE" shall mean the eighteen month anniversary of the
Conversion Commencement Date.

            "SECOND CALL REDEMPTION PRICE" shall mean $50.84 per unit (as such
price may be adjusted pursuant to Section 6(d)).

            "SPECIAL CALL REDEMPTION PRICE" shall mean the following based upon
the date on which the Special Call Option is exercised:

                                                              SPECIAL CALL
       SPECIAL CALL REDEMPTION PRICE                     OPTION EXERCISED BEFORE
       -----------------------------                     -----------------------

    Greater of 126% of Closing                                June 25, 2006
    Price or 107% of Market
    Price on Redemption Date ("Redemption
    Date Market Price")

    Greater of 125% of Closing                               October 7, 2006
    Price or 106% of Redemption
    Date Market Price

    Greater of 124% of Closing                              January 20, 2007
    Price or 105% of Redemption
    Date Market Price

    Greater of 123% of Closing                                 May 4, 2007
    Price or 104% of Redemption
    Date Market Price

                                                              SPECIAL CALL
            SPECIAL CALL PRICE                           OPTION EXERCISED BEFORE
            ------------------                           -----------------------

    Greater of 122% of Closing                               August 16, 2007
    Price or 103% of Redemption
    Date Market Price

    Greater of 121% of Closing                              November 28, 2007
    Price or 102% of Redemption
    Date Market Price


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    Greater of 120% of Closing                             The First Call Date
    Price or 101% of Redemption
    Date Market Price


            "TRADING DAY" shall mean a day on which there is trading on the New
York Stock Exchange or such other market or exchange on which the Preferred Unit
is then principally traded.

            "VOTING STOCK" of any person as of any date means the equity
interests of such person pursuant to which the holders thereof have the general
voting power under ordinary circumstances to elect at least a majority of the
board of directors, managers, general partners or trustees of such person
(regardless of whether, at the time, equity interests of any other class or
classes shall have, or might have, voting power by reason of the occurrence of
any contingency) or, with respect to a partnership (whether general or limited),
any general partner interest in such partnership.

         3. Dividends. Commencing on the Dividend Commencement Date, the Holders
of the Preferred Units shall be entitled to receive cumulative dividends at the
per unit rate of six and a half percent (6.5%) per annum of the Face Value of
each outstanding Preferred Unit. Dividends shall be paid on the same date (a
"DIVIDEND PAYMENT Date") as the dividend payment date for Common Units and the
record dates for dividends on the Preferred Units and Common Units shall be the
same. Dividends shall accrue on each Dividend Payment Date. Notwithstanding
anything in this Section 3 to the contrary, with respect to Preferred Units
which are converted with Common Units, the Holder shall not be entitled to a
Preferred Unit dividend and a Common Unit dividend with respect to the same
period, but shall be entitled only to the dividend to be paid based upon the
class of equity held on the record date. Thus, if Holder converts Preferred
Units into Common Units prior to a record date, on the applicable Dividend
Payment Date, it shall receive the Common Unit dividend with respect to such
units and if the Holder converts Preferred Units after a record date, on the
applicable Dividend Payment Date, it shall receive the Preferred Unit dividend.

         4. LIQUIDATION VALUE. In the event of any liquidation, dissolution or
winding up of the Company, either voluntary or involuntary, the Holders of the
Preferred Units shall be entitled to receive, out of the assets of the Company
available for distribution to unit holders, prior and in preference to any
distribution of any assets of the Company to the holders of any other class or
series of equity securities, the amount of Face Value per unit plus all accrued
but unpaid dividends thereon and all liquidated damages payable under the
Registration Rights Agreement (as defined below) which have not yet been paid
(collectively, the "LIQUIDATION VALUE"). The foregoing shall not affect any
rights which Holders of Preferred Units may have with respect to any requirement
that the Company repurchase the Preferred Units or for any right to monetary
damages.

         5. ISSUANCE OF PREFERRED UNITS. The Preferred Units shall be issued by
the Company pursuant to a Purchase Agreement, dated on or about the date hereof
(the "PURCHASE AGREEMENT") between the Company and the initial subscriber for
the Preferred Units thereunder (collectively, the "SUBSCRIBER"), and Holders of
Preferred Units shall enjoy the benefits of the Registration Rights Agreement,
dated on or about the date hereof (the "REGISTRATION RIGHTS AGREEMENT") between
such parties in connection with the Purchase Agreement to the extent set forth
therein.


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         6. CONVERSION.

            a) Conversion at Option of Holders. Commencing on the Conversion
Commencement Date, subject to the terms hereof, each Holder of the Preferred
Units shall have the right at any time and from time to time, at the option of
such Holder, to request conversion of any or all Preferred Units held by such
Holder for such number of fully paid, validly issued and nonassessable Common
Units, free and clear of any liens, claims or encumbrances, as is determined by
dividing (i) the Liquidation Value times the number of Preferred Units being
converted, by (ii) the applicable Conversion Price on the Conversion Notice Date
(subject to the limitations set forth in this Section 6). Immediately following
such conversion, the rights of the Holders of converted Preferred Units,
including without limitation, any accrual of dividends, shall cease and the
persons entitled to receive the Common Units upon the conversion of Preferred
Units shall be treated for all purposes as having become the owners of such
Common Units.

            b) Mandatory Conversion. On the Mandatory Conversion Date, all then
outstanding Preferred Units shall be automatically converted into Common Units,
determined in the manner set forth in paragraph (a) above; provided however,
that the applicable Conversion Price shall be the Conversion Price based on the
ten Trading Days immediately preceding the Mandatory Conversion Date; provided,
however, that in lieu of converting the Preferred Units, the Company may
exercise the Currency Conversion Option, provided that has provided the Holder
with written notice of such exercise no later than 10 Trading Days prior to the
Mandatory Conversion Date.

            c) Mechanics of Conversion. To convert Preferred Units into Common
Units, the Holder shall give written notice ("CONVERSION NOTICE") to the Company
in the form of page 1 of Exhibit A hereto (which Conversion Notice may be given
by facsimile transmission) stating that such Holder elects to convert the same
and shall state therein the number of Preferred Units to be converted; provided
that such number must be at least the lesser of 10,000 or the number of
outstanding Preferred Units, and the name or names in which such Holder wishes
the certificate or certificates for Common Units to be issued. The date of the
Conversion Notice shall be hereinafter be referred to as the "CONVERSION NOTICE
DATE." The Holder may not submit more than one Conversion Notice during any 30
day period. No later than 5 Trading Days after receipt of the Conversion Notice,
the Company shall notify Holder in writing (the "COMPANY NOTICE") of its option
to either (i) issue Common Units to Holder or (ii) pay to Holder the Conversion
Value of the Preferred Units in cash pursuant to the Currency Conversion Option.
The Company shall then either issue the Common Units or pay the Conversion Value
of the Preferred Units being redeemed, as indicated to the Holder, on a date
(the "CONVERSION DATE") no later than 30 days after Conversion Notice Date. In
the event that the Company shall have elected to issue Common Units, the Company
shall, in the Company Notice, indicate its computation of the number of Common
Units to be received by Holder. On the Conversion Date and subject to the
book-entry provisions set forth below, such Holder shall surrender the


                                       6
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certificate or certificates representing the Preferred Units being converted,
duly endorsed, at the office of the Company or, if identified in writing to
Holder by the Company, at the offices of any transfer agent for such units. If
the Company shall have elected to pay the Conversion Value to Holders on the
Conversion Date, it shall wire Federal Funds in the amount of the Conversion
Value to the account of the Holder specified by Holder to the Company. If the
Company has elected to issue Common Units, then on the Conversion Date, the
Company shall issue Holder a certificate or certificates for the number of
Common Units to which such Holder shall be entitled (with the number of and
denomination of such certificates designated by such Holder), and the Company
shall immediately issue and deliver to such Holder a certificate or certificates
for the number of Preferred Units (including any fractional shares) which such
Holder has not yet elected to convert hereunder but which are evidenced in part
by the certificate(s) delivered to the Company in connection with such
Conversion Notice. If certificates evidencing the Common Units are not received
by the Holder within five (5) Trading Days of the Conversion Date, then the
Holder will be entitled to: (i) revoke and withdraw its Conversion Notice, in
whole or in part, at any time prior to its receipt of those certificates or (ii)
be paid immediately the Conversion Value by the Company instead of receiving
Common Units. In lieu of delivering physical certificates representing the
Common Units issuable upon conversion of Preferred Units, provided the Company's
transfer agent is participating in the Depository Trust Company ("DTC") Fast
Automated Securities Transfer ("FAST") program, upon request of the Holder, the
Company shall use its best efforts to cause its transfer agent to electronically
transmit the Common Units issuable upon conversion or dividend payment to the
Holder, by crediting the account of the Holder's prime broker with DTC through
its Deposit Withdrawal Agent Commission ("DWAC") system. The time periods for
delivery described above, shall apply to the electronic transmittals through the
DWAC system. The parties agree to coordinate with DTC to accomplish this
objective. The conversion pursuant to this Section 6 shall be deemed to have
been made immediately prior to the close of business on the Conversion Date. The
person or persons entitled to receive the Common Units issuable upon such
conversion shall be treated for all purposes as the record Holder or Holders of
such Common Units at the close of business on the Conversion Date.

            The Company's obligation to issue Common Units upon conversion of
Preferred Units shall, subject to compliance with this subsection (a) in all
material respects, be absolute, is independent of any covenant of any Holder of
Preferred Units, and shall not be subject to: (i) any offset or defense; or (ii)
any claims against the Holders of Preferred Units whether pursuant to this
Certificate of Designations, the Purchase Agreement, the Registration Rights
Agreement, or otherwise.

            Book-Entry. Notwithstanding anything to the contrary set forth
herein, upon conversion of any Preferred Units in accordance with the terms
hereof, the Holder thereof shall not be required to physically surrender such
Holder's certificates for Preferred Units to the Company unless such Holder is
converting all of the Preferred Units then held by such Holder. The Holders of
Preferred Units and the Company shall maintain records showing the number of
Preferred Units so converted hereunder, the number of Common Units received upon
conversion and the dates of such conversions, or shall use such other method,
reasonably satisfactory to the Holders and the Company, so as not to require
physical surrender of certificates for Preferred Units upon each such
conversion. Notwithstanding the foregoing, if any Preferred Units are converted
as aforesaid, such Holder of Preferred Units may not transfer its Preferred
Units unless such Holder first physically surrenders to the Company all
certificates representing any Preferred Units which have previously been
converted in whole or in part, whereupon the Company will forthwith issue and
deliver upon the order of such Holder new certificate(s) evidencing Preferred
Units, registered as such Holder may request, representing in the aggregate,
together with all other certificates evidencing Preferred Units held by such
Holder, the remaining number of Preferred Units held by such Holder. Each Holder
of Preferred Units (and any successor in interest or assignee), by acceptance of
Preferred Units, acknowledges that, by reason of the provisions of this
paragraph, following conversion of any Preferred Units, the number of Preferred
Units actually owned by such Holder may be less than the number of Preferred
Units set forth on the face of the certificates representing Preferred Units and
held by such Holder.


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            d) Conversion Adjustments.

               (i) If the Company or any of its subsidiaries, at any time while
            the Preferred Units are outstanding (A) shall pay a unit dividend or
            otherwise make a distribution or distributions on any equity
            securities (including instruments or securities convertible into or
            exchangeable for such equity securities) in Common Units, (B)
            subdivide outstanding Common Units into a larger number of units, or
            (C) combine outstanding Common Units into a smaller number of units,
            then each Affected Price (as defined below) shall be multiplied by a
            fraction, the numerator of which shall be the number of Common Units
            outstanding before such event and the denominator of which shall be
            the number of Common Units outstanding after such event. Any
            adjustment made pursuant to this Section 6(d)(i) shall become
            effective immediately after the record date for the determination of
            unit holders entitled to receive such dividend or distribution and
            shall become effective immediately after the effective date in the
            case of a subdivision or combination.

               As used herein, the Affected Prices (each an "AFFECTED PRICE")
            shall refer to: (i) the Closing Price, First Call Redemption Price,
            Second Call Redemption Price or Low Price (as defined in Section
            7(f)); or, as applicable, (ii) each closing price for Common Units
            occurring on any Trading Day included in the period used for
            determining the Market Price, which Trading Day occurred before the
            record date in the case of events referred to in clause (A) of this
            subparagraph 6(d)(i) and before the effective date in the case of
            the events referred to in clauses (B) and (C) of this subparagraph
            6(d)(i).

               (ii) If the Company or any of its subsidiaries, at any time while
            the Preferred Units are outstanding, shall distribute to all holders
            of Common Units evidences of its indebtedness or assets or cash
            (other than the Company's regularly declared and scheduled dividend)
            or rights or securities (excluding those referred to in Section
            6(d)(i) above and 6(d)(iii) below) or warrants to subscribe for or
            purchase any security of the Company or any of its subsidiaries
            (excluding those referred to in Section 6(d)(i) above and 6(d)(iii)
            below), then each Affected Price shall be adjusted by multiplying
            the existing Affected Price, by a fraction, (A) the numerator of
            which is the closing price per Common Unit immediately prior to the
            record date fixed for determination of Holders of Common Units
            entitled to receive the distribution (the "REFERENCE PRICE") less
            the fair market value per Common Unit at such record date of the
            distribution as reasonably determined by the General Partner in good
            faith and (B) the denominator of which is the Reference Price;
            provided, however, that if the Holder disputes the General Partner's
            valuation above, the Holder and the Company shall select a mutually
            acceptable appraiser (the "APPRAISER") whose fee shall be borne
            equally by the Holder and the Company, and the fair market value of
            such distribution shall be as determined by the Appraiser.


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               (iii) Prior to the consummation of any recapitalization,
            reorganization, consolidation, merger, spin-off or other business
            combination (other than a Change in Control Transaction) pursuant to
            which holders of Common Units are entitled to receive securities or
            other assets with respect to or in exchange for Common Units (a
            "COMPANY EVENT"), the Company shall make appropriate provision to
            insure that the Holder will thereafter have the right to receive
            upon a conversion of its Preferred Units at the Conversion Price in
            lieu of the Common Units otherwise receivable upon such conversion,
            such securities or other assets received by the holders of Common
            Units in connection with the consummation of such Company Event in
            such amounts as the Holder would have been entitled to receive had
            the Preferred Units initially been issued with a conversion rights
            for the form of such consideration (as opposed to Common Units) at a
            conversion ratio for such consideration equal to a fraction, the
            numerator of which is the outstanding Liquidation Value multiplied
            by the number of outstanding Preferred Units and the denominator of
            which is the Conversion Price. Provision made pursuant to the
            preceding sentence shall be in a form and substance satisfactory to
            the Holders.

               (iv) In case of any Change of Control, then without limiting
            other rights hereunder, the Holder shall have the right thereafter
            to, at its option, (A) convert Preferred Units, in whole or in part,
            at the Conversion Price, into the units and other securities, cash
            and/or property receivable upon or deemed to be held by holders of
            Common Units following such Change of Control, and such conversion
            shall be effected on the closing of the Change of Control (B)
            subject to Section 4.08 of the Indenture, dated as of December 20,
            2005, by and among the Company, its subsidiaries named therein and
            Wachovia Bank, National Association relating to the Company's 8-?%
            Senior Notes due 2015 (the "SENIOR NOTES"), require the Company or
            its successor to redeem, within five days of notice to the Company,
            the Preferred Units, in whole or in part, at a redemption price
            equal to the greater of (x) the Liquidation Value of the Preferred
            Units or (y) the Conversion Value of the Preferred Units. To the
            extent that Holder does not exercise its option described in the
            immediately preceding sentence, the terms of any such Change in
            Control Transaction shall include such terms so as to continue to
            give to the Holders the right to receive the amount of securities,
            cash and/or property upon any conversion or redemption following
            such Change in Control Transaction to which a holder of the number
            of Common Units deliverable upon such conversion would have been
            entitled in such Change in Control Transaction. This provision shall
            similarly apply to successive reclassifications, consolidations,
            mergers, sales, transfers or share exchanges. Holder's right to
            convert pursuant to clause (A) above shall be irrespective of
            whether it has previously submitted a Conversion Notice within the
            prior 30 days.


                                       9
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            e) Notice of Record Date. In the event of any taking by the Company
of a record date of the holders of any class of securities for the purpose of
determining the holders thereof who are entitled to receive any dividend or
other distribution, any security or right convertible into or entitling the
holder thereof to receive additional Common Units, or any right to subscribe
for, purchase or otherwise acquire any shares of stock of any class or any other
securities or property, or to receive any other right, the Company shall notify
each Holder of Preferred Units at least 15 days prior to the record date, of
which any such record is to be taken for the purpose of such dividend,
distribution, security or right and the amount and character of such dividend,
distribution, security or right; provided, however, that the foregoing
requirement shall be deemed satisfied if at least 15 days prior to record date,
the Company shall have issued a press release which shall be posted on the
Company's website and carried by one or more wire services, containing the
required information.

            f) Issue Taxes. The Company shall pay any and all issue,
documentary, stamp and other taxes, excluding any income, franchise or similar
taxes, that may be payable in respect of any issue or delivery of Common Units
on conversion of, or payment of dividends on, Preferred Units pursuant hereto.
However, the Holder of any Preferred Units shall pay any tax that is due because
the Common Units issuable upon conversion thereof or dividend payment thereon
are issued in a name other than such Holder's name.

            G) [INTENTIONALLY OMITTED]

            h) Fractional Units. No fractional Common Units shall be issued upon
the conversion of any Preferred Units. All Common Units (including fractions
thereof) issuable upon conversion of more than one Preferred Unit by a Holder
thereof shall be aggregated for purposes of determining whether the conversion
would result in the issuance of any fractional unit. If, after the
aforementioned aggregation, the conversion would result in the issuance of a
fraction of a Common Unit, the Company shall, in lieu of issuing any fractional
unit, either round up the number of units to the next highest whole number or,
at the Company's option, pay the Holder otherwise entitled to such fraction a
sum in cash equal to the fair market value of such fraction on the Conversion
Date (as determined in good faith by the General Partner of the Company).

            i) Specific Enforcement. The Company agrees that irreparable damage
would occur in the event that any of the provisions of this Certificate of
Designations were not performed in accordance with their specific terms or were
otherwise breached. Each Holder shall have all rights and remedies set forth in
this Certificate and all rights and remedies which such Holders have been
granted at any time under any other agreement or contract and all of the rights
which such Holders have under any law. Any person having any rights under any
provision of this Certificate shall be entitled to enforce such rights
specifically or pursue other injunctive relief or other equitable remedies
(without posting a bond or other security), to recover damages by reason of any
breach of any provision of this Certificate and to exercise all other rights
granted by law. Each Holder without prejudice may withdraw, revoke or suspend
its pursuit of any remedy at any time prior to its complete recovery as a result
of such remedy.


                                       10
<PAGE>

            j) Conversion Limitations.

               (A) 9.9% Limitation. Notwithstanding anything to the contrary
         contained herein, the number of Common Units that may be acquired by
         the Holder upon conversion pursuant to the terms hereof shall not
         exceed a number that, when added to the total number of Common Units
         deemed beneficially owned by such Holder (other than by virtue of the
         ownership of securities or rights to acquire securities (including the
         Preferred Units) that have limitations on the Holder's right to
         convert, exercise or purchase similar to the limitation set forth
         herein), as determined pursuant to the rules and regulations
         promulgated under Section 13(d) of the Exchange Act, including all
         Common Units deemed beneficially owned at such time (other than by
         virtue of the ownership of securities or rights to acquire securities
         that have limitations on the right to convert, exercise or purchase
         similar to the limitation set forth herein) by persons that would be
         aggregated for purposes of determining whether a group under Section
         13(d) of the Exchange Act, exists, would exceed 9.9% of the total
         issued and outstanding Common Units (the "RESTRICTED OWNERSHIP
         PERCENTAGE"). The Holder shall have the right (w) at any time and from
         time to time to reduce its Restricted Ownership Percentage immediately
         upon notice to the Company and (x) (subject to waiver) at any time and
         from time to time, to increase its Restricted Ownership Percentage
         immediately in the event of the announcement as pending or planned, of
         a Change in Control Transaction. If, pursuant to a mandatory conversion
         pursuant to Section 6(b) herein the Company elects to issue Common
         Units to Holder, and as a result Holder would otherwise exceed the
         Restricted Ownership Percentage, then with respect to the Common Units
         that would cause the Restricted Ownership Percentage to be exceeded,
         the Company shall pay in cash to Holder an amount equal to the Market
         Price multiplied by the number of excess Common Units ("EXCESS
         AMOUNT").

               (B) Principal Market Regulation. The Company shall not be
         obligated to issue any Common Units upon conversion of the Preferred
         Units, whether pursuant to this Section 6, or otherwise, if the
         issuance of such Common Units would exceed that number of units of
         Common Units which the Company may issue upon conversion of the
         Preferred Units without breaching the Company's obligations under the
         rules or regulations of the Principal Market (the "PRINCIPAL MARKET
         CAP"). To the extent that the Preferred Units are converted for a
         number of Common Units that would exceed the Principal Market Cap, the
         Company shall pay in cash to Holder the Excess Amount.

         7. COMPANY REDEMPTION RIGHTS.

            a) Prior to the First Call Date, the Company shall have the option
(the "SPECIAL CALL OPTION"), subject to the conditions set forth below, to
redeem all, but not less than all, of the Preferred Units for an aggregate cash
amount equal to the product of (A) the Liquidation Value of the outstanding
Preferred Units divided by the Conversion Price; multiplied by (B) the Special
Call Redemption Price.


                                       11
<PAGE>

            b) The exercise of the Special Call Option by the Company shall be
subject to the following conditions: (i) transmission of a written notice
("SPECIAL CALL OPTION NOTICE") no sooner than 20 Trading Days prior to the
Redemption Date, which notice shall specify the Redemption Date; and (ii) if the
Redemption Date shall occur after the Conversion Commencement Date, the
satisfaction of the Call Option Conditions on the 20 consecutive Trading Days
immediately preceding the date of the Special Call Option Notice and at all
times from such date to the applicable Redemption Date.

            c) The Company shall have the option (the "CALL OPTION") to (A) on
or after the First Call Date but no later than the Second Call Date redeem some
or all of the outstanding Preferred Units for cash, for an amount determined by
dividing the Liquidation Value of the Preferred Units being redeemed by the
Conversion Price and multiplying by the First Call Redemption Price; and (B) on
or after the Second Call Date, redeem some or all outstanding Preferred Units
for cash, for an amount determined by dividing the Liquidation Value of the
Preferred Units being redeemed by the Conversion Price and multiplying by the
Second Call Redemption Price; provided, however, that the foregoing redemptions
must be exercised for no less than the lesser of: (x) 10,000 Preferred Units, or
(y) the number of remaining outstanding Preferred Units. However, the foregoing
right shall not affect the right of the Holder to convert Preferred Units
pursuant to the terms of Section 6(a) with respect to any Conversion Notice
submitted by Holder prior to a Redemption Date and the conversion of such
Preferred Units shall be governed by the provisions of Section 6(a) and not this
Section 7.

            d) The exercise of the Call Option by the Company shall be subject
to: (i) the transmission of a written notice of the exercise of the Call Option
to the Holder (the "CALL OPTION NOTICE") no later than 10 Trading Days prior to
the applicable Redemption Date which shall specify the amount of Preferred Units
being redeemed; and (ii) the satisfaction of the Call Option Conditions on the
20 Trading Days immediately preceding the Call Option Notice and at all times
from the Call Option Notice to the applicable Redemption Date.

            e) With respect to exercises of the Special Call Option and the Call
Option, on the applicable Redemption Date, the Company shall remit the
applicable cash consideration to the Holder. The Holder shall deliver to the
Company the certificates representing the Preferred Units as soon as
practicable, following the applicable Redemption Date.

            f) (i) In addition, the Company shall have the option (the "LOW
PRICE REDEMPTION OPTION") to redeem all of the Preferred Units if at any time
(including the period prior to the Conversion Commencement Date), the closing
price for the Common Units shall be less than $36 (as adjusted pursuant to
Section 6(d)) (the "LOW PRICE") for 10 consecutive Trading Days (a "LOW PRICE
TRADING PERIOD")

               (ii) If a Low Price Trading Period shall have occurred, then,
            until the earlier of: (A) 5 Trading Days from the end of the Low
            Price Trading Period or (B) the first Trading Day following the Low
            Price Trading Period for which the closing price shall be above the
            Closing Price (as adjusted pursuant to Section 6(d)), the Company
            may exercise the Trading Price Redemption Option by written notice
            to the Holder. Such notice (the "LOW PRICE REDEMPTION NOTICE") shall
            specify the applicable redemption date (the "LOW PRICE REDEMPTION
            DATE") which shall be no more than 30 days from the date of the Low
            Price Redemption Notice.


                                       12
<PAGE>

               (iii) On the Low Price Redemption Date, if prior to the Dividend
            Commencement Date, the Company shall pay to the Holder in cash the
            Liquidation Value of the Preferred Units plus an amount equal to the
            greater of: (A) an 8% annualized return on the Face Value from the
            issuance date; (B) an 8% annualized return on the Face Value for one
            quarter (collectively, the "LOW PRICE REDEMPTION PRICE"). If the Low
            Price Redemption Date occurs after the Dividend Commencement Date,
            the Company shall pay Holder the amount set forth above less the
            amount of dividend payments made on the Preferred Units.

               (iv) The Company's non-exercise of the Low Price Redemption
            Option shall not affect Holder's right to convert Preferred Units
            pursuant to Section 6(a) above. If the Company exercises the Low
            Price Redemption Option, Holder may still convert any or all
            Preferred Units pursuant to the terms of Section 6(a) if Holder
            delivers a Conversion Notice prior to the Low Price Redemption Date
            and the Low Price Redemption Date occurs after the Conversion
            Commencement Date.

         8. VOTING RIGHTS. In addition to all other requirements imposed by
Delaware law, and all other voting rights granted under the Company's Limited
Partnership Agreement, the affirmative vote of a majority of the Company's
outstanding Preferred Units shall be necessary for repeal of this Certificate of
Designations or the Certificate of Limited Partnership or Limited Partnership
Agreement or any amendment to the Limited Partnership or Limited Partnership
Agreement (including any merger or consolidation) that may materially amend or
change or adversely affect any of the rights, preferences, obligations or
privileges of the Preferred Units provided, however, that Holders of Preferred
Units who are affiliates of the Company (and the Company itself) shall not
participate in such vote and the Preferred Units of such Holders shall be
disregarded and deemed not to be outstanding for purposes of such vote.

         9. NOTICES. The Company shall distribute to the Holders of Preferred
Units copies of all notices, materials, annual and quarterly reports, proxy
statements, information statements and any other documents distributed generally
to the holders of Common Units of the Company, at such times and by such method
as such documents are distributed to such holders of such Common Units.

         10. CERTIFICATES.

             a) The certificate(s) representing the Preferred Units held by any
Holder of Preferred Units may be exchanged by such Holder at any time and from
time to time for certificates with different denominations representing an equal
aggregate number of Preferred Units, as reasonably requested by such Holder,
upon surrendering the same. No service charge will be made for such registration
or transfer or exchange. In the event that any Holder of Preferred Units
notifies the Company that its certificate(s) therefor have been lost, stolen or
destroyed, the Company shall promptly and without charge deliver replacement
certificate(s) to such Holder, provided that such Holder executes and delivers
to the Company an agreement reasonably satisfactory to the Company to indemnify
the Company from any loss incurred by it in connection with such lost, stolen or
destroyed certificate(s).


                                       13
<PAGE>

             b) The certificate(s) representing the Preferred Units may be
imprinted with a legend in substantially the following form:

         "THIS CERTIFICATE IS NOT REQUIRED TO BE PHYSICALLY SURRENDERED TO THE
         COMPANY IN THE EVENT THAT THE SECURITIES REPRESENTED BY THIS
         CERTIFICATE ARE CONVERTED OR REDEEMED IN PART. AS A RESULT, FOLLOWING
         ANY CONVERSION OR REDEMPTION OF ANY PORTION OF THE SECURITIES
         REPRESENTED BY THIS CERTIFICATE, THE SECURITIES REPRESENTED BY THIS
         CERTIFICATE MAY BE LESS THAN THE NUMBER OF UNITS INDICATED ON THIS
         CERTIFICATE. IF ANY SECURITIES ARE CONVERTED AS AFORESAID, THE HOLDER
         OF THIS CERTIFICATE MAY NOT TRANSFER ANY SECURITIES REPRESENTED BY THIS
         CERTIFICATE UNLESS AND UNTIL SUCH HOLDER FIRST PHYSICALLY SURRENDERS TO
         ATLAS PIPELINE PARTNERS, L.P. ALL CERTIFICATES REPRESENTING ANY SUCH
         SECURITIES WHICH HAVE PREVIOUSLY BEEN CONVERTED IN WHOLE OR IN PART,
         WHEREUPON ATLAS PIPELINE PARTNERS WILL FORTHWITH ISSUE AND DELIVER UPON
         THE ORDER OF SUCH HOLDER NEW CERTIFICATE(S) EVIDENCING SUCH SECURITIES
         THEN HELD BY SUCH HOLDER."

         11. [Intentionally Omitted]

         12. NO REISSUANCE. No Preferred Units acquired by the Company by reason
of redemption, purchase, conversion or otherwise shall be reissued.

         13. NO SENIOR SECURITIES. So long as any Preferred Units remain
outstanding, the Company and its subsidiaries shall not, without the affirmative
vote of the Holders of at least 75% of the outstanding Preferred Units, issue
any equity securities ranking senior to the Preferred Units with respect to
liquidation preference, dividends, the timing of redemption or voting rights.

         14. SEVERABILITY OF PROVISIONS. If any right, preference or limitation
of the Preferred Units set forth in this Certificate of Designations (as this
Certificate of Designations may be amended from time to time) is invalid,
unlawful or incapable of being enforced by reason of any rule or law or public
policy, all other rights, preferences and limitations set forth in this
Certificate of Designations, which can be given effect without the invalid,
unlawful or unenforceable right, preference or limitation shall nevertheless
remain in full force and effect, and no right, preference or limitation herein
set forth be deemed dependent upon any such other right, preference or
limitation unless so expressed herein.

                                    * * * * *
                            [Signature Page Follows]


                                       14
<PAGE>




         IN WITNESS WHEREOF, this Certificate of Designations of the Company has
been duly executed this 13th day of March, 2006.



                                         ATLAS PIPELINE PARTNERS, L.P.

                                         By: ATLAS PIPELINE PARTNERS GP, LLC
                                               General Partner


                                             By:
                                                 ----------------------------




                                       15
<PAGE>



                                    EXHIBIT A

                            (To be Executed by Holder
                      in order to Convert Preferred Units)

                                CONVERSION NOTICE
                                       FOR
                   6.5% CUMULATIVE CONVERTIBLE PREFERRED UNITS


The undersigned, as a holder ("Holder") of 6.5% Cumulative Convertible Preferred
Units ("Preferred Units") of Atlas Pipeline Partners, L.P. (the "Company"),
hereby irrevocably elects to convert _____________ Preferred Units for Common
Units of the Company according to the terms and conditions of the Certificate of
Designations for the Preferred Units as of the date written below. The
undersigned hereby requests that certificates for the Common Units to be issued
to the undersigned pursuant to this Conversion Notice be issued in the name of,
and delivered to, the undersigned or its designee as indicated below. No fee
will be charged to the Holder of Preferred Units for any conversion. Capitalized
terms used herein and not otherwise defined shall have the meanings ascribed
thereto in the Certificate of Designations.


Conversion Information:       NAME OF HOLDER:

                           By:
                           Print Name:
                           Print Title:

                           Print Address of Holder:
                           _____________________________________________________
                           _____________________________________________________

                           Issue Common Units to:_______________________________
                           at:__________________________________________________
                           _____________________________________________________



If Common Units are to be issued to a person other than Holder, Holder's
signature must be guaranteed below:

SIGNATURE GUARANTEED BY:




THE COMPUTATION OF NUMBER OF COMMON UNITS TO BE RECEIVED IS SET FORTH ON PAGE 2
OF THE CONVERSION NOTICE.

                           PAGE 1 OF CONVERSION NOTICE


                                       16
<PAGE>



PAGE 2 TO CONVERSION NOTICE DATED _________________ FOR: _______________________
                                  (CONVERSION DATE)         (NAME OF HOLDER)


              COMPUTATION OF NUMBER OF COMMON UNITS TO BE RECEIVED

Number of Preferred Units converted:       ________________ shares

<TABLE>
<S>                                                                     <C>
          Number of Preferred Units converted x Liquidation Value       $


TOTAL DOLLAR AMOUNT CONVERTED                                           $
                                                                        =================



CONVERSION PRICE                                                        $

Number of Common Units   =    Total dollar amount converted        =    _____________
                              -----------------------------
                                   Conversion Price

            NUMBER OF COMMON UNITS   =
</TABLE>

If the conversion is not being settled by DTC, please issue and deliver _____
certificate(s) for Common Units in the following amount(s):

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If the Holder is receiving certificate(s) for Preferred Units upon the
conversion, please issue and deliver _____ certificate(s) for Preferred Units in
the following amounts:

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