<PAGE>   1
                                                                     EXHIBIT 4.2


                            CERTIFICATE OF AMENDMENT

                           CERTIFICATE OF DESIGNATION

                                       OF

                 SERIES A CONVERTIBLE REDEEMABLE PREFERRED STOCK

                                       OF

                                RAILAMERICA, INC.

                         (PURSUANT TO SECTION 151 OF THE
                        DELAWARE GENERAL CORPORATION LAW)

                      ------------------------------------


         RailAmerica, Inc., a corporation organized and existing under the
General Corporation Law of the State of Delaware (hereinafter called the
"Corporation"), hereby certifies that the following resolution was adopted by
the Board of Directors of the Corporation as required by Section 151 of the
Business Corporation Law by unanimous written consent dated December 28, 1998:

         RESOLVED, that pursuant to the authority granted to and vested in the
Board of Directors of this Corporation (hereinafter called the "Board of
Directors" or the "Board") in accordance with the provisions of the Certificate
of Incorporation of the Corporation, the Board of Directors hereby creates a
Series A Convertible Redeemable Preferred Stock, $.001 par value per share (the
"Series A Preferred Stock"), of the Corporation and hereby states the
designation and number of shares, and fixes the relative rights, preferences,
and limitations thereof as follows:

         Series A Convertible Redeemable Preferred Stock:

         Section 1. DESIGNATION AND AMOUNT. The shares of such series shall be
designated as "Series A Convertible Redeemable Preferred Stock" (the "Series A
Preferred Stock") and the number of shares constituting the Series A Preferred
Stock shall be 1,000,000. Such number of shares may be increased or decreased by
resolution of the Board of Directors; provided, that no decrease shall reduce
the number of shares of Series A Preferred Stock to a number less than the
number of shares then outstanding and no increase shall increase the number of
shares of Series A Preferred Stock above the total number of authorized shares.

         Section 2. RANK. The Series A Preferred Stock shall rank as to
distributions of assets upon liquidation, dissolution or winding up of the
Corporation, whether voluntary or involuntary: (i) senior to all of the
Corporation's common stock, par value $.001 per share (the "Common Stock"); (ii)
senior to any class or series of capital stock of the Corporation hereafter
created specifically ranking by its terms junior to the Series A Preferred Stock
(collectively, with the Common Stock, "Junior Securities" or "Junior Stock");
and (iii) on parity with any class or series of capital stock of the Corporation
hereafter created specifically ranking by its terms on parity with the Series A
Preferred Stock ("Parity Securities" or "Parity Stock"). While any shares of
Series A Preferred Stock are outstanding, no Parity Securities or





                                       
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equity securities senior to the Series A Preferred Stock shall be authorized or
issued without the approval (by vote or written consent, as provided by law) of
the holders of at least a majority of the then outstanding shares of the Series
A Preferred Stock, voting as a class. This prohibition shall not include the
authorization or issuance of any form of debt securities or instruments to a
bank or other institution.

         Section 3.        DIVIDENDS.

                           (a) The holders of the Series A Preferred Stock shall
be entitled to receive out of funds of the Corporation legally available for
payment cash dividends, payable semi-annually in arrears, at the rate of $1.875
per share per annum, payable in cash. Dividends on the Series A Preferred Stock
shall accrue from the date of issuance or thereafter, from the most recent date
on which dividends were payable, and shall be payable semi-annually on, June 30
and December 31 of each year (each a "Dividend Payment Date"), commencing on
June 30, 1999; provided, however, that if any such day is a non-business day,
the Dividend Payment Date will be the next business day. Each declared dividend
shall be payable to holders of record as they appear at the close of business on
the stock books of the Corporation on May 10 and December 10 of each year (each
of such dates a "Record Date"). Semi-annual dividend periods (each a "Dividend
Period") shall commence on and include the 1st day of July and January of each
year and shall end on and include the day next preceding the next following
Dividend Payment Date.

                           (b) No dividends shall be declared or paid or set
apart for payment on any Common Stock, Parity Stock or Junior Stock during any
semi-annual period unless full dividends on the Series A Preferred Stock for all
Dividend Periods ending prior to or during such semi-annual period have been or
contemporaneously are declared and paid or declared and a sum sufficient for the
payment thereof is set apart for such payment. When dividends are not so paid in
full (or a sum sufficient for such full payment is not so set apart) upon the
Series A Preferred Stock and any other Parity Stock, dividends upon the Series A
Preferred Stock and dividends on such other Parity Stock payable during such
semi-annual period shall be declared pro rata so that the amount of such
dividends so payable per share on the Series A Preferred Stock and such other
Parity Stock shall in all cases bear to each other the same ratio that full
dividends on the shares of Series A Preferred Stock and full dividends, if any,
on shares of such other Parity Stock, bear to each other. If full dividends on
the Series A Preferred Stock have not been declared and paid or set apart for
payment, no dividend or distribution, other than in shares of Junior Stock, may
be declared, set aside or paid on any shares of Junior Stock. Holders of the
Series A Preferred Stock shall not be entitled to any dividends, whether payable
in cash, property or stock, in excess of the dividends provided for herein. No
interest or sum of money in lieu of interest shall be payable in respect of any
declared dividend payment or payments on the Series A Preferred Stock which may
be in arrears. As used herein, the phrase "set apart" in respect of the payment
of dividends shall require deposit of any funds in a bank or trust company in a
separate deposit account maintained for the benefit of the holders of the Series
A Preferred Stock.

         Section 4. VOTING RIGHTS. The holders of Series A Preferred Stock will
have no voting rights except as required by law, except that the affirmative
vote of the holders of a majority of the outstanding shares of Series A
Preferred Stock is necessary for the issuance of Senior Securities or Parity
Securities, the authorization or issuance of securities convertible into such
Senior Securities or Parity Securities, or the amendment to the Corporation's
Certificate of Incorporation so as to adversely affect the Series A Preferred
Stock, or waiver of any other covenants.






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         To the extent that under Delaware law the vote of the holders of shares
of Series A Preferred Stock, voting separately as a class, is required to
authorize a given action of the Corporation, the affirmative vote or consent of
the holders of at least a majority of the outstanding shares of the Series A
Preferred Stock shall constitute the approval of such action by the class.

         Section 5. CONVERSION. Subject to and upon compliance with this Section
5, the holders of shares of Series A Preferred Stock shall have conversion
rights as follows:

                           (a) OPTIONAL CONVERSION. Each holder of a share of
Series A Preferred Stock shall have the right, at any time, at the office of the
Corporation or any transfer agent for the Series A Preferred Stock, to convert
such share of Series A Preferred Stock into that number of fully paid and
nonassessable shares of Common Stock equal to $25.00 divided by the Conversion
Price of such share of Series A Preferred Stock as set forth in Section 6
hereof. The number of share of Common Stock into which the Series A Preferred
Stock may be invested is hereinafter referred to as the "Conversion Rate."

                           (b) MECHANICS OF CONVERSION. In order to convert
shares of Series A Preferred Stock into shares of Common Stock, the holder of
shares of Series A Preferred Stock shall (i) fax or otherwise deliver a copy of
the fully executed notice of conversion in the form attached hereto as Exhibit A
("Notice of Conversion") to the Corporation at its principal office and to the
office of its designated transfer agent that such holder elects to convert the
same, which notice shall specify the number of shares of Series A Preferred
Stock to be converted and shall contain the Conversion Price (together with a
copy of the first page of each certificate to be converted) prior to 5:00 p.m.,
Eastern Standard time (the "Conversion Notice Deadline") on the date of
conversion specified on the Notice of Conversion and (ii) surrender the original
certificate or certificates for the shares of Series A Preferred Stock to be
converted, duly endorsed, and deliver the original Notice of Conversion by
either overnight courier or two-day courier, to the principal office of the
Corporation or to the office of its designated transfer agent; provided,
however, that the Corporation shall not be obligated to issue certificates
evidencing the shares of Common Stock issuable upon such conversion unless the
certificates evidencing such shares of Series A Preferred Stock are delivered to
the Corporation or its transfer agent as provided above. Upon receipt by the
Corporation of evidence of the loss, theft, destruction or mutilation of any
certificate representing shares of Series A Preferred Stock, and (in the case of
loss, theft or destruction) of indemnity or security reasonably satisfactory to
the Corporation, and upon surrender and cancellation of any certificate
representing shares of Series A Preferred Stock, if mutilated, the Corporation
shall execute and deliver a new certificate of like tenor and date. No
fractional shares of Common Stock shall be issued upon conversion of the Series
A Preferred Stock. In lieu of any fractional share to which the holder of shares
of Series A Preferred Stock would otherwise be entitled, the Corporation shall
pay cash to such holder in an amount equal to such fraction multiplied by the
Conversion Price then in effect. In the case of a dispute as to the calculation
of the Conversion Rate, the Corporation's calculation shall be deemed conclusive
absent manifest error.

         The Corporation shall use all reasonable efforts to issue and deliver
within seven (7) business days after delivery to the Corporation of the
certificates representing the shares of Series A Preferred Stock to be
converted, or after such agreement and indemnification, to such holder of Series
A Preferred Stock at the address of the holder on the books of the Corporation,
a certificate or certificates for the number of shares of Common Stock to which
the holder shall be entitled as aforesaid. The date on which conversion occurs
(the "Date of Conversion") shall be deemed to be the date set forth in such
Notice of Conversion, provided (i) that the advance copy of the Notice of
Conversion is delivered to and received 






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by the Corporation before 5:00 p.m., Eastern Standard time, on the Date of
Conversion, and (ii) that the original stock certificates representing the
shares of Series A Preferred Stock to be converted are received by the
Corporation or the transfer agent within two (2) business days thereafter. The
person or persons entitled to receive the shares of Series A Preferred Stock
issuable upon such conversion shall be treated for all purposes as the record
holder or holders of such shares of Common Stock on the Date of Conversion. If
the original certificates representing the shares of Series A Preferred Stock to
be converted are not received by the Corporation or the transfer agent within
two (2) business days after the Date of Conversion or if the facsimile of the
Notice of Conversion is not received by the Corporation or its transfer agent
prior to the Conversion Notice Deadline, the Notice of Conversion, at the
Corporation's option, may be declared null and void.

         Following any conversion of shares of Series A Preferred Stock, such
shares of Series A Preferred Stock shall no longer be outstanding and all rights
of a holder with respect to the shares surrendered for conversion shall
immediately terminate except for the right to receive Common Stock.

                           (c) RESERVATION OF SHARES. The Corporation shall at
all times reserve and keep available out of its authorized but unissued shares
of Common Stock such number of shares of Common Stock as shall from time to time
be sufficient to effect the conversion of all then outstanding shares of Series
A Preferred Stock; and if at any time the number of authorized but unissued
shares of Common Stock shall not be sufficient to effect the conversion of all
then outstanding shares of Series A Preferred Stock, the Corporation will take
such corporate action as may be necessary to increase its authorized but
unissued shares of Common Stock to such number of shares as shall be sufficient
for such purpose.

         Section 6. CONVERSION PRICE. The "Conversion Price" per share of the
Series A Preferred Stock shall be $8.25, subject to adjustment as set forth
below.

                           (a) If, prior to the conversion of all outstanding
shares of Series A Preferred Stock, the number of outstanding shares of Common
Stock is increased by a stock split, stock dividend or other similar event, the
Conversion Price shall be proportionately reduced, or if the number of
outstanding shares of Common Stock is decreased by a combination or
reclassification of shares or other similar event, the Conversion Price shall be
proportionately increased.

                           (b) Subject to Section 8(c) hereof, if, prior to the
conversion of all outstanding shares of Series A Preferred Stock, there shall be
any merger, consolidation, exchange of shares, recapitalization, reorganization
or other similar event, as a result of which shares of Common Stock of the
Corporation shall be changed into the same or a different number of shares of
the same or another class or classes of stock or securities of the Corporation
or another entity, then the holders of shares of Series A Preferred Stock shall
thereafter have the right to purchase and receive upon conversion of Series A
Preferred Stock, upon the basis and upon the terms and conditions specified
herein and in lieu of the shares of Common Stock immediately theretofore
issuable upon conversion, such shares of stock and/or securities as may be
issued or payable with respect to or in exchange for the number of shares of
Common Stock immediately theretofore purchasable and receivable upon the
conversion of the Series A Preferred Stock held by such holders had such merger,
consolidation, exchange of shares, recapitalization or reorganization not taken
place, and in any such case appropriate provisions shall be made with respect to
the rights and interests of the holders of the Series A Preferred Stock to the
end that the provisions hereof (including, without limitation, provisions for
adjustment of 





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the Conversion Price and of the number of shares issuable upon conversion of the
Series A Preferred Stock) shall thereafter be applicable, as nearly as may be
practicable in relation to any shares of stock or securities thereafter
deliverable upon the exercise hereof. The Corporation shall not effect any
transaction described in this subsection 6(b) unless the resulting successor or
acquiring entity (if not the Corporation) assumes by written instrument the
obligation to deliver to the holders of the Series A Preferred Stock such shares
of stock and/or securities as, in accordance with the foregoing provisions, the
holders of the Series A Preferred Stock may be entitled to purchase.

                           (c) No adjustment of the Conversion Price shall be
made in an amount less than $.01 per share.

                           (d) Upon any adjustment of the Conversion Price, then
and in each case the Corporation shall give written notice thereof, by first
class mail, postage prepaid, addressed to each holder of shares of the Series A
Preferred Stock at the address of such holder as shown on the books of the
Corporation, which notice shall state the Conversion Price resulting from such
adjustment, setting forth in reasonable detail the method of calculation and the
facts upon which such calculation is based.

         Section 7. STATUS OF CONVERTED OR REACQUIRED SHARES. Any shares of
Series A Preferred Stock converted into shares of Common Stock pursuant to
Section 5 hereof or purchased or otherwise acquired by the Corporation in any
manner whatsoever shall be retired and canceled promptly after the conversion or
acquisition thereof. All such shares shall upon their cancellation become
authorized but unissued shares of Series A Preferred Stock and may be reissued
as part of a new series of preferred stock subject to the conditions and
restrictions on issuance set forth herein, in the Certificate of Incorporation,
or in any other Certificate of Designation creating a series of preferred stock
or any similar stock or as otherwise required by law.

         Section 8.        LIQUIDATION, DISSOLUTION OR CHANGE OF CONTROL.

                           (a) In the event of any liquidation, dissolution or
winding up of the Corporation, either voluntary or involuntary, the holders of
shares of Series A Preferred Stock shall be entitled to receive out of the
assets of the Corporation available for distribution to stockholders under
applicable law, prior and in preference to any distribution to holders of the
Common Stock or any Junior Securities but in parity with any distribution to
holders of Parity Securities, an amount of $25.00 per share (the "Liquidation
Value"), plus a sum equal to all dividends accrued on such shares (whether or
not declared) and unpaid for the then current Dividend Period. If upon the
occurrence of such event, the assets and funds to be distributed among the
holders of shares of Series A Preferred Stock and Parity Securities shall be
insufficient to permit the payment to such holders of the full preferential
amounts due to the holders of shares of Series A Preferred Stock and Parity
Securities, respectively, then the entire assets and funds of the Corporation
legally available for distribution shall be distributed among the holders of
shares of Series A Preferred Stock and Parity Securities, pro rata, based on the
respective liquidation amounts to which each such series of stock is entitled by
the Corporation's Certificate of Incorporation and any certificate of
designation of preferences.

                           (b) Upon the completion of the distribution required
by subsection 8(a) above, if assets remain in the Corporation, they shall be
distributed to holders of Parity Securities (unless holders of Parity Securities
have received distributions pursuant to subsection 8(a)) and Junior Securities
in accordance with the Corporation's Certificate of Incorporation, including any
duly adopted certificate(s) of designation of preferences.





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                           (c) (i) Upon a Change of Control (as defined below)
of the Corporation, each holder of the Series A Preferred Stock will have the
option to require the Corporation to repurchase such holder's shares of Series A
Preferred Stock at a price per share equal to the Liquidation Value plus any
accrued and unpaid dividends. A "Change of Control" shall have occurred: (A)
when any person or group is or becomes the beneficial owner of 50% or more of
the then outstanding voting shares of the Corporation, (B) when, during any
period of two consecutive years after the initial closing of the offering of the
Series A Preferred Stock, individuals who at the beginning of such period
constituted the Corporation's Board of Directors, or whose nomination for
election by the Corporation's stockholders was approved by a vote of a majority
of the directors of the Corporation then still in office who were either
directors at the beginning of such period or whose election or nomination for
election was previously so approved, cease for any reason to constitute a
majority of the directors then in office or (C) upon any sale, transfer or other
conveyance of all or substantially all of the assets of the Corporation.

                                    (ii) Upon the occurrence of a Change of
         Control, the Corporation will offer to repurchase (the "Change of
         Control Purchase Offer") all outstanding shares of Series A Preferred
         Stock, and each holder of outstanding shares of Series A Preferred
         Stock will have the right to require that the Company repurchase such
         holder's shares of Series A Preferred Stock, at the price set forth in
         clause (i) of this subsection 8(c). Within 30 days following any Change
         of Control, the Corporation shall mail a notice, by first class mail,
         to each holder of record of Series A Preferred Stock (a "Change of
         Control Notice"), at his address of record, stating:

                                            (A) that a Change of Control has
                           occurred and that such holder has the right to
                           require the Corporation to purchase such holder's
                           shares of Series A Preferred Stock at the price set
                           forth above;

                                            (B) the circumstances and relevant
                           facts regarding such Change of Control;

                                            (C) the date on which the
                           Corporation will repurchase any shares of Series A
                           Preferred Stock which the holders require the
                           Corporation to repurchase in accordance with this
                           subsection 8(c), which date shall be no earlier than
                           30 days nor later than 60 days from the date such
                           Change of Control Notice is mailed (the "Change of
                           Control Purchase Date");

                                            (D) that, unless the Corporation
                           defaults in making such payment, any shares of Series
                           A Preferred Stock accepted for payment pursuant to
                           the Change of Control Purchase Offer shall cease to
                           accrue dividends after the Change of Control Purchase
                           Date;

                                            (E) that holders of Series A
                           Preferred Stock electing to have their shares
                           repurchased pursuant to any Change of Control
                           Purchase Offer shall be required to surrender the
                           original certificates for the shares of Series A
                           Preferred Stock at the address specified in the
                           notice, at least three business days before the
                           Change of Control Purchase Date; and



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                                            (F) that the holders of Series A
                           Preferred Stock shall be entitled to withdraw their
                           election if the Corporation receives, not later than
                           the last business day prior to the Change of Control
                           Purchase Date, a telegram, telex, facsimile
                           transmission or letter setting forth the name of the
                           holder, the number of shares of Series A Preferred
                           Stock the holder delivered for repurchase and a
                           statement that such holder is withdrawing his
                           election to have such shares repurchased.

                                    (iii) Each holder of shares of Series A
         Preferred Stock electing to have such shares purchased by the
         Corporation pursuant to this subsection 8(c) shall deliver to the
         Corporation at its principal office, at least three business days prior
         to the Change of Control Purchase Date, the original certificate or
         certificate(s) for the shares to be purchased duly endorsed, together
         with written notice to the Corporation specifying the number of shares
         of Series A Preferred Stock to be purchased. Holders of Series A
         Preferred Stock will be entitled to withdraw their election if the
         Corporation receives, not later than one business day prior to the
         Change of Control Purchase Date, a telegram, facsimile transmission or
         letter, at its principal office, setting forth the name of the holder,
         the number of shares of Series A Preferred Stock which were delivered
         by the holder for purchase by the Corporation and a statement that such
         holder is withdrawing his election to have such shares purchased.

                                    (iv) Promptly following the Change of
         Control Purchase Date, the Corporation will mail or deliver to each
         holder of shares of Series A Preferred Stock who properly tendered such
         shares to the Corporation for purchase pursuant to this subsection 8(c)
         and did not withdraw such holder's election, at his address of record,
         an amount equal to the purchase price for the shares of Series A
         Preferred Stock so delivered for purchase as set forth in this
         subsection 8(c). Unless the Corporation shall have defaulted in the
         payment of the purchase price for shares of Series A Preferred Stock
         tendered for purchase by the Corporation, all rights of the holders of
         such shares (except the right to receive the purchase price therefor)
         shall cease with respect to such shares on the Change of Control
         Purchase Date and such shares shall not, after the Change of Control
         Purchase Date, be deemed to be outstanding and shall not have the
         status of Series A Preferred Stock.

                                    (v) The Corporation will comply, to the
         extent applicable, with the requirements of Section 14(e) of the
         Securities Exchange Act of 1934, as amended, and any other applicable
         securities laws or regulations in connection with the repurchase of
         Series A Preferred Stock pursuant to this subsection 8(c). To the
         extent that the provisions of any securities laws or regulations
         conflict with the provisions of this subsection 8(c), the Corporation
         will comply with the applicable securities laws and regulations and
         will not be deemed to have breached its obligations under this Section
         by virtue thereof.

         Section 9. CONSOLIDATION, MERGER, ETC. Except as set forth in Section
8(c) hereof, in the event of a merger, reorganization, recapitalization or
similar event of or with respect to the Corporation (a "Corporate Change")
(other than a Corporate Change in which all or substantially all of the
consideration received by the holders of the Corporation's equity securities
upon such Corporate Change consists of cash or assets other than securities
issued by the acquiring entity or any affiliate thereof), the Series A Preferred
Stock shall be assumed by the acquiring entity and thereafter the Series A
Preferred Stock shall be convertible into such class and type of securities as
the holder of shares of Series A 





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Preferred Stock would have received had such holder converted the Series A
Preferred Stock immediately prior to such Corporate Change.

         Section 10.       REDEMPTION.

                           (a) OPTIONAL REDEMPTION. If the average closing price
of the Common Stock, as reported on the Nasdaq Stock Market, equals or exceeds
150% of the Conversion Price for any ten (10) trading days within a thirty (30)
consecutive trading day period, the Corporation may, at its option, redeem the
Series A Preferred Stock, at a redemption price per share equal to the
Liquidation Value plus accrued and unpaid dividends. Each holder of Series A
Preferred Stock will be given notice of such redemption and will have the right
to convert the Series A Preferred Stock into shares of Common Stock prior to the
redemption date specified in such notice.

                           (b) MANDATORY REDEMPTION. The Corporation will be
required to redeem the outstanding shares of Series A Preferred Stock on
December 31, 2003, at a redemption price per share equal to the Liquidation
Value plus accrued and unpaid dividends.

                           (c) MECHANICS OF REDEMPTION. Notice of redemption of
the Series A Preferred Stock, specifying the redemption date and place of
redemption, shall be given by first class mail to each holder of record of the
shares to be redeemed, at his address of record, not less than 30 nor more than
60 calendar days prior to the date upon which the Corporation shall redeem the
Series A Preferred Stock (the "Redemption Date"). Each such notice shall also
specify the redemption price applicable to the shares to be redeemed. If less
than all the shares owned by such holder are then to be redeemed, the notice
shall also specify the number of shares thereof which are to be redeemed and the
fact that a new certificate or certificates representing any unredeemed shares
shall be issued without cost to such holder.

                                    (i) Notice of redemption of shares of the
         Series A Preferred Stock having been given as provided in Section
         10(b), then unless the Corporation shall have defaulted in the payment
         of the redemption price and all accrued and unpaid dividends (whether
         or not declared), all rights of the holders thereof (except the right
         to receive the redemption price and all accrued and unpaid dividends,
         whether or not declared) shall cease with respect to such shares on the
         Redemption Date and such shares shall not, after the Redemption Date,
         be deemed to be outstanding and shall not have the status of Series A
         Preferred Stock. In case fewer than all the shares represented by any
         such certificate are redeemed, a new certificate shall be issued
         representing the unredeemed shares without cost to the holder thereof.

                                    (ii) Shares of the Series A Preferred Stock
         are not subject or entitled to the benefit of a sinking fund.

                                    (iii) Notwithstanding the foregoing, if
         notice of redemption shall have been given pursuant to this Section 10
         and any holder of the Series A Preferred Stock shall, prior to the
         close of business on the date three business days next preceding the
         Redemption Date, give written notice to the Corporation pursuant to
         Section 5 hereof of the conversion of any or all of the shares held by
         the holder (accompanied by a certificate or certificates for such
         shares, duly endorsed or assigned to the Corporation), then the
         redemption shall not become effective as to such shares and the
         conversion shall become effective as provided in Section 5.



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         IN WITNESS WHEREOF, this Certificate of Designation has been executed
on behalf of the Corporation by its Chairman of the Board this 29th day of
December, 1998.

                                      RAILAMERICA, INC.


                                      By: /s/ GARY O. MARINO          
                                          ---------------------------------
                                                    Gary O. Marino
                                          Chairman of the Board of Directors

































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                                                                       EXHIBIT A

                              NOTICE OF CONVERSION

                    (TO BE EXECUTED BY THE REGISTERED HOLDER

                IN ORDER TO CONVERT THE SERIES A PREFERRED STOCK)

         The undersigned hereby irrevocably elects to convert ______ shares of
Series A Preferred Stock, represented by stock certificate No(s).
________________ (the "Series A Preferred Stock Certificates") into shares of
common stock ("Common Stock") of RailAmerica, Inc. (the "Corporation") according
to the conditions of the Certificate of Designation of Series A Preferred Stock,
as of the date written below. If shares are to be issued in the name of a person
other than the undersigned, the undersigned will pay all transfer taxes payable
with respect thereto. No fee will be charged to the holder for any conversion,
except for transfer taxes, if any.

         The undersigned represents and warrants that all offers and sales by
the undersigned of the shares of Common Stock issuable to the undersigned upon
conversion of the Series A Preferred Stock shall be made pursuant to
registration of such shares of Common Stock under the Securities Act of 1933, as
amended, or pursuant to an exemption from registration under such Act.

Conversion Calculations:                                     
                                            Date of Conversion
                                            Applicable Conversion Price
                                            Signature
                                            Name
                                            Address:

*No shares of Common Stock will be issued until the original Series A Preferred
Stock Certificate(s) to be converted and the Notice of Conversion are received
by the Corporation or its designated Transfer Agent. The original Stock
Certificate(s) representing the Series A Preferred Stock to be converted and the
Notice of Conversion must be received by the Corporation or its designated
Transfer Agent by the second business day following the Date of Conversion, or
the Notice of Conversion, at the Corporation's option, may be declared null and
void.