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                                                                [EXECUTION COPY]

                                                                     Exhibit 4.5


                         ASSET BRIDGE WARRANT AGREEMENT

         ASSET BRIDGE WARRANT AGREEMENT, dated as of February 4, 2000 (as
amended, supplemented, amended and restated or otherwise modified from time to
time, this "WARRANT AGREEMENT"), between RAILAMERICA, INC., a Delaware
corporation ("HOLDINGS"), and the purchasers set forth on the signature pages
hereto (the "PURCHASERS"). Capitalized terms used herein and not defined herein
shall have the meanings specified in the Asset Bridge Securities Purchase
Agreement described below.


                                    RECITALS

         WHEREAS, Palm Beach Rail Holding, Inc., a Delaware corporation
(together with its successors,"INTERMEDIATE HOLDINGS"), Holdings and the other
Guarantors set forth therein and the Purchasers have entered into an Asset
Bridge Securities Purchase Agreement, dated as of February 4, 2000 (as amended,
supplemented or otherwise modified, the "ASSET BRIDGE SECURITIES PURCHASE
AGREEMENT"), pursuant to which the Purchasers have agreed to purchase up to
$55,000,000 in aggregate principal amount of the Asset Bridge Senior Secured
Increasing Rate Notes (the "NOTES") of Intermediate Holdings, subject to the
terms and conditions set forth in the Asset Bridge Securities Purchase
Agreement;

         WHEREAS, as a condition precedent to the purchase of the Asset Bridge
Notes by the Purchasers, Holdings has agreed to issue, and the Purchasers are
entitled to receive (on the terms and conditions, and pursuant to the schedules,
set forth in the Asset Bridge Escrow Agreement referred to below) warrants, as
hereinafter described (the "WARRANTS"), to purchase an amount of Common Stock,
$0.001 par value per share, of Holdings (the "COMMON STOCK") or any security
substituted for the Common Stock in an amount equal to up to the percentage of
the Capital Stock of Holdings as of the Issuance Date as set forth on Schedule 1
hereto (such Common Stock being referred to herein as the "WARRANT SHARES"), at
an exercise price equal to the closing price per share of Common Stock of
Holdings traded on the NASDAQ National Market System at the close of trading on
the Issuance Date (the "EXERCISE PRICE");

         WHEREAS, Holdings has agreed that the holders of Asset Bridge Notes
shall be entitled to receive, in accordance with the Asset Bridge Escrow
Agreement, Warrants representing (x) 50% of the total Warrants placed in escrow
on the date that is 180 days following the Issuance Date, (y) 25% of the total
Warrants placed in escrow on the date that is 270 days following the Issuance
Date and (z) 25% of the total Warrants placed in escrow on the date that is 360
days following the Issuance Date; and




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         WHEREAS, Holdings has agreed to execute the Warrants and deliver the
Warrants to an escrow agent on the date hereof and such escrow agent has agreed
to deliver the Warrants to the holders of Asset Bridge Notes in accordance with
an Asset Bridge Escrow Agreement dated as of February 4, 2000 (as amended,
supplemented or otherwise modified, the "ASSET BRIDGE ESCROW AGREEMENT") among
Holdings, the Purchasers and Snoga, Inc., as escrow agent.

         NOW, THEREFORE, in consideration of the premises and the mutual
agreements herein set forth, the parties hereto agree as follows:


                                    AGREEMENT

         SECTION 1. WARRANT CERTIFICATES. The certificates evidencing the
Warrants (the "WARRANT CERTIFICATES") to be delivered pursuant to this Agreement
shall be in registered form only and shall be substantially in the form set
forth in EXHIBIT A attached hereto.

         SECTION 2. EXECUTION OF WARRANT CERTIFICATES. Warrant Certificates
shall be signed on behalf of Holdings by its chief executive officer, its
president, any vice-president, its chief financial officer or, if Holdings shall
not have a chief financial officer, its treasurer (each an "OFFICER"). Each such
signature upon the Warrant Certificates may be in the form of a facsimile
signature of the present or any future Officer and may be imprinted or otherwise
reproduced on the Warrant Certificates and for that purpose Holdings may adopt
and use the facsimile signature of any person who shall have been an Officer,
notwithstanding the fact that at the time the Warrant Certificates shall be
delivered or disposed of he shall have ceased to hold such office.

         In case any Officer of Holdings who shall have signed any of the
Warrant Certificates shall cease to be such Officer before the Warrant
Certificates so signed shall have been delivered or disposed of by Holdings,
such Warrant Certificates nevertheless may be delivered or disposed of as though
such person had not ceased to be such Officer of Holdings.

         SECTION 3. REGISTRATION. Holdings shall number and register each
Warrant Certificate in a register (the "WARRANT REGISTER") as such Warrant
Certificate is issued. Holdings may deem and treat the registered holder(s) of
the Warrant Certificates as the absolute owners thereof (notwithstanding any
notation of ownership or other writing thereon made by anyone), for all
purposes, and shall not be affected by any notice to the contrary.

         SECTION 4. REGISTRATION OF TRANSFERS AND EXCHANGES. Holdings shall from
time to time register the transfer of any outstanding Warrant Certificates in
the Warrant Register to be maintained by Holdings upon surrender thereof
accompanied by a written instrument or instruments of transfer in form
satisfactory to Holdings, duly executed by the registered holder or holders
thereof or by the duly appointed legal representative thereof or by a duly
authorized attorney. Upon any such registration of transfer, a new Warrant
Certificate shall be issued to the



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transferee(s) and the surrendered Warrant Certificate shall be canceled and
disposed of by Holdings.


         The Warrant holders agree that prior to any proposed transfer of the
Warrant or of the Warrant Shares, if such transfer is not made pursuant to an
effective Registration Statement under the Securities Act, the Warrant holder
will, if requested by Holdings, deliver to Holdings:

                  (1) an investment covenant reasonably satisfactory to Holdings
         signed by the proposed transferee;

                  (2) an agreement by such transferee to the placement of the
         restrictive investment legend set forth below on the Warrant or the
         Warrant Shares;

                  (3) an agreement by such transferee that Holdings may place a
         notation in the stock books of Holdings or a "stop transfer order" with
         any transfer agent or registrar with respect to the Warrant Shares;

                  (4) an agreement by such transferee to be bound by the
         provisions of this SECTION 4 relating to the transfer of such Warrant
         or Warrant Shares; and

                  (5) an opinion of the proposed transferee's counsel
         (reasonably satisfactory to Holdings) addressed to Holdings to the
         effect that the proposed Transfer of such Asset Bridge Notes may be
         effected without registration under the Securities Act.

         The Warrant holders agree that each certificate representing Warrants
and Warrant Shares will bear the following legend:

         "THE SECURITIES EVIDENCED OR CONSTITUTED HEREBY HAVE BEEN ACQUIRED FOR
         INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
         1933, AS AMENDED. SUCH SECURITIES MAY NOT BE SOLD, TRANSFERRED, PLEDGED
         OR HYPOTHECATED UNLESS THE REGISTRATION PROVISIONS OF SAID ACT AND ANY
         APPLICABLE STATE SECURITIES LAWS HAVE BEEN COMPLIED WITH OR UNLESS
         HOLDINGS HAS RECEIVED AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO
         HOLDINGS THAT SUCH REGISTRATION IS NOT REQUIRED."

         Warrant Certificates may be exchanged at the option of the holder(s)
thereof when surrendered to Holdings at its office for another Warrant
Certificate or other Warrant Certificates of like tenor and representing in the
aggregate a like number of Warrants. Warrant Certificates surrendered for
exchange shall be canceled and disposed of by Holdings.



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         SECTION 5. TERMS OF WARRANTS: EXERCISE OF WARRANTS. Subject to the
terms of this Agreement, each Warrant holder shall have the right, which may be
exercised commencing at the opening of business on the relevant Exercise Date
and until 5:00 p.m. New York City time on the seventh anniversary of such
Exercise Date, to receive from Holdings the number of fully paid and
nonassessable Warrant Shares which the holder may at the time be entitled to
receive on exercise of such Warrant and payment of the Exercise Price for such
Warrant Shares. For purposes hereof, "Exercise Date" means, for any Warrant, the
date upon which such Warrant was released from escrow pursuant to the terms of
the Asset Bridge Escrow Agreement.

         A Warrant may be exercised upon surrender to Holdings at its office
designated for such purpose (the address of which is set forth in SECTION 14
hereof) of the certificate or certificates evidencing the Warrants to be
exercised with the form of election to purchase on the reverse thereof duly
filled in and signed, which signature shall be guaranteed by a bank or trust
company having an office or correspondent in the United States or a broker or
dealer which is a member of a registered securities exchange or the National
Association of Securities Dealers, Inc. (the "NASD"), and upon payment to
Holdings of the Exercise Price. Payment of the Exercise Price shall be made (i)
in cash or by certified or official bank check payable to the order of Holdings,
(ii) by tendering Warrants having a fair market value equal to the Exercise
Price or (iii) with any combination of CLAUSE (I) or (II). For purpose of CLAUSE
(II) above, the fair market value of the Warrants shall be determined as
follows: (A) to the extent the Common Stock is publicly traded and listed on the
NASDAQ National Market System, or a national securities exchange, the fair
market value shall be equal to the difference between (1) the Quoted Price of
the Common Stock on the date of exercise and (2) the Exercise Price; or (B) to
the extent the Common Stock is not publicly traded, or otherwise is not listed
on a national securities exchange, the fair market value of the Warrants shall
be equal to the difference between (1) the value per share of Common Stock as
determined in good faith by the Board of Directors of Holdings pursuant to
CLAUSE (N) of SECTION 10 and (2) the Exercise Price.

         Subject to the provisions of SECTION 6 hereof, upon such surrender of
Warrants and payment of the Exercise Price, Holdings shall issue and cause to be
delivered with all reasonable dispatch, but in no event later than three
Business Days after such surrender and payment, to or upon the written order of
the holder and in such name or names as the Warrant holder may designate, a
certificate or certificates for the number of full Warrant Shares issuable upon
the exercise of such Warrants as provided in SECTION 10; PROVIDED, that if any
consolidation, merger or lease or sale of assets is proposed to be effected by
Holdings as described in CLAUSE (M) of SECTION 10 hereof, or a tender offer or
an exchange offer for shares of Common Stock of Holdings shall be made, upon
such surrender of Warrants and payment of the Exercise Price as aforesaid,
Holdings shall, as soon as possible, but in any event not later than two
Business Days thereafter, issue and cause to be delivered the full number of
Warrant Shares issuable upon the exercise of such Warrants in the manner
described in this sentence as provided in SECTION 10. Together with the delivery
of such Warrant Shares, Holdings shall deliver a certificate of its chief
accounting or chief financial officer or, if Holdings shall not have a chief
financial officer, its


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controller setting forth and certifying the calculations made by Holdings
pursuant to SECTION 10 hereof to determine the number of Warrant Shares issuable
upon the exercise of the surrendered Warrant or Warrants. Such certificate or
certificates representing Warrant Shares shall be deemed to have been issued and
any person so designated to be named therein shall be deemed to have become a
holder of record of such Warrant Shares as of the date of the surrender of such
Warrants and payment of the Exercise Price.

         The Warrants shall be exercisable, at the election of the holders
thereof, either in full or from time to time in part and, in the event that a
certificate evidencing Warrants is exercised in respect of fewer than all of the
Warrant Shares issuable on such exercise at any time prior to the date of
expiration of the Warrants, a new certificate evidencing the remaining Warrant
or Warrants will be issued and delivered pursuant to the provisions of this
Section and of SECTION 2 hereof; PROVIDED, that Warrants may not be exercised in
denominations of less than 1,000 unless the holder has fewer than 1,000
Warrants.

         All Warrant Certificates surrendered upon exercise of Warrants shall be
canceled and disposed of by Holdings.

         Holdings shall keep copies of this Agreement and any notices given or
received hereunder available for inspection by the holders during normal
business hours at its office.

         SECTION 6. PAYMENT OF TAXES. Holdings shall pay all documentary stamp
taxes attributable to the initial issuance of Warrant Shares upon the exercise
of Warrants; PROVIDED, that Holdings shall not be required to pay any tax or
taxes which may be payable in respect of any transfer involved in the issue of
any Warrant Certificates or any certificates for Warrant Shares in a name other
than that of the registered holder of a Warrant Certificate surrendered upon the
transfer or exercise of a Warrant, and Holdings shall not be required to issue
or deliver such Warrant Certificates or Warrant Shares unless or until the
person or persons requesting the issuance thereof shall have paid to Holdings
the amount of such tax or shall have established to the satisfaction of Holdings
that such tax has been paid.

         SECTION 7. MUTILATED OR MISSING WARRANT CERTIFICATES. In case any of
the Warrant Certificates shall be mutilated, lost, stolen or destroyed, Holdings
may in its discretion issue, in exchange and substitution for and upon
cancellation of the mutilated Warrant Certificate, or in lieu of and
substitution for the Warrant Certificate lost, stolen or destroyed, a new
Warrant Certificate of like tenor and representing an equivalent number of
Warrants, but only upon receipt of evidence reasonably satisfactory to Holdings
of such loss, theft or destruction of such Warrant Certificate and indemnity, if
requested, also reasonably satisfactory to it. Applicants for such substitute
Warrant Certificates shall also comply with such other reasonable regulations
and pay such other reasonable charges as Holdings may prescribe.


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         SECTION 8. RESERVATION OF WARRANT SHARES. Holdings shall at all times
reserve and keep available, free from preemptive rights, out of the aggregate of
its authorized but unissued Common Stock or its authorized and issued Common
Stock held in its treasury for the purpose of enabling it to satisfy any
obligation to issue Warrant Shares upon exercise of Warrants, the maximum number
of shares of Common Stock which may then be deliverable upon the exercise of all
outstanding Warrants.

         Holdings or, if appointed, the transfer agent for the Common Stock (the
"TRANSFER AGENT") and every subsequent transfer agent for any shares of
Holdings' Capital Stock issuable upon the exercise of any of the rights of
purchase aforesaid will be irrevocably authorized and directed at all times to
reserve such number of authorized shares as shall be required for such purpose.
Holdings will keep a copy of this Agreement on file with the Transfer Agent and
with every subsequent transfer agent for any shares of Holdings' Capital Stock
issuable upon the exercise of the rights of purchase represented by the
Warrants. Holdings will furnish such Transfer Agent a copy of all notices of
adjustments and certificates related thereto, transmitted to each holder
pursuant to SECTION 13 hereof.

         Before taking any action which would cause an adjustment pursuant to
SECTION 10 or 11 hereof in the Exercise Rate (as defined below), Holdings will
take any corporate action which may, in the opinion of its counsel, be necessary
in order that Holdings may validly and legally issue fully paid and
nonassessable Warrant Shares at the Exercise Rate as so adjusted.

         Holdings covenants that all Warrant Shares which may be issued upon
exercise of Warrants will, upon issue, be fully paid, nonassessable, free of
preemptive rights and free from all taxes, liens, charges and security interests
with respect to the issue thereof.

         SECTION 9. OBTAINING STOCK EXCHANGE LISTINGS. Without limiting any term
or condition of the Asset Bridge Equity Registration Rights Agreement, Holdings
will from time to time take all action which may be necessary so that the
Warrant Shares, immediately following their issuance upon the exercise of
Warrants, will be listed on the principal securities exchanges and markets
within the United States of America, if any, on which other shares of Common
Stock are then listed.

         SECTION 10. ADJUSTMENT OF NUMBER OF WARRANT SHARES ISSUABLE. The number
of Warrant Shares issuable upon the exercise of each Warrant (the "EXERCISE
RATE") is subject to adjustment from time to time upon the occurrence of the
events enumerated in this SECTION 10 and under the circumstances described in
SECTION 11. For purposes of this SECTION 10, "Common Stock" means shares now or
hereafter authorized of any class of common stock of Holdings and any other
Capital Stock of Holdings, however designated, that has the right (subject to
any prior rights of any class or series of preferred stock) to participate in
any distribution of the assets or earnings of Holdings without limit as to per
share amount.



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         (a) ADJUSTMENT FOR CHANGE IN CAPITAL STOCK. If Holdings:

                  (1) pays a dividend or makes a distribution on its Common
         Stock in shares of its Common Stock;

                  (2) subdivides its outstanding shares of Common Stock into a
         greater number of shares;

                  (3) combines its outstanding shares of Common Stock into a
         smaller number of shares;

                  (4) makes a distribution on its Common Stock in shares of its
         Capital Stock other than Common Stock; or

                  (5) issues by reclassification of its Common Stock any shares
         of its Capital Stock;

then the Exercise Rate in effect immediately prior to such action shall be
proportionately adjusted so that the holder of any Warrant thereafter exercised
may receive the aggregate number and kind of shares of Capital Stock of Holdings
which he would have owned immediately following such action if such Warrant had
been exercised immediately prior to such action.

         The adjustment shall become effective immediately after the record date
in the case of a dividend or distribution and immediately after the effective
date in the case of a subdivision, combination or reclassification.

         If after an adjustment a holder of a Warrant upon exercise of such
Warrant may receive shares of two or more classes of Capital Stock of Holdings,
Holdings shall determine in good faith the allocation of the adjusted Exercise
Rate between the classes of Capital Stock. After such allocation, the exercise
privilege and the Exercise Rate of each class of Capital Stock shall thereafter
be subject to adjustment on terms comparable to those applicable to Common Stock
in this Section.

         Such adjustment shall be made successively whenever any event listed
above shall occur.

         (b) ADJUSTMENT FOR RIGHTS ISSUE. If Holdings issues any rights, options
or warrants entitling any person to subscribe for Common Stock or securities
convertible into, or exchangeable or exercisable for, Common Stock at an
offering price (or with an initial conversion, exchange or exercise price plus
such offering price) that is less than the Current Market Price per share of






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Common Stock on the record date for such issuance (all of the foregoing,
"RIGHTS"), the Exercise Rate shall be adjusted in accordance with the formula:

     E' = E  x  O + N
                -----------
                     N x P
                O +  -----
                      M

where:

         E'   =   the adjusted Exercise Rate.

         E    =   the current Exercise Rate.

         O    =   the number of shares of Common Stock outstanding on
                  the record date (assuming the conversion, exercise or
                  exchange of all Rights and convertible securities
                  into shares of Common Stock).

         N    =   the number of additional shares of Common Stock
                  issuable pursuant to the Rights offered.

         P    =   the offering price plus initial conversion,
                  exchange or exercise price per share of the
                  additional shares of Common Stock issuable pursuant
                  to the Rights.

         M   =    the Current Market Price per share of Common Stock
                  on the record date.

         The adjustment shall be made successively whenever any such Rights are
issued and shall become effective immediately after the record date for the
determination of stockholders entitled to receive the Rights in the case of
Rights to be issued to the holders of Common Stock. To the extent that shares of
Common Stock are not delivered after the expiration of such Rights, the Exercise
Rate shall be readjusted to the Exercise Rate which would otherwise be in effect
had the adjustment made upon the issuance of such options, rights or warrants
been made on the basis of delivery of only the number of shares of Common Stock
actually delivered. In the event that such options, rights or warrants are not
so issued, the Exercise Rate shall again be adjusted to be the Exercise Rate
which would then be in effect if such date fixed for determination of
stockholders entitled to receive such options, rights or warrants had not been
so fixed.

         This CLAUSE (B) does not apply to:

                  (1) Rights issued to persons in a bona fide public offering
         pursuant to a firm commitment underwriting,

                  (2) Rights issued to persons who are not affiliates of
         Holdings in a bona fide private placement through a placement agent
         that is a member firm of the NASD (except to the extent that any
         discount from the Current Market Price attributable to restrictions





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         on transferability of the Rights, as determined in good faith by the
         Board of Directors pursuant to CLAUSE (N) of SECTION 10 and described
         in a Board resolution, shall exceed 5%), or

                  (3) Rights issued to Holdings employees under bona fide
         employee benefit plans adopted by the Board of Directors and approved
         by the holders of Common Stock when required by law, if such Rights
         would otherwise be covered by this CLAUSE (B) (but only to the extent
         that the aggregate number of Rights excluded hereby and issued after
         the date of this Agreement shall not exceed the right to subscribe for
         more than 5% of the Common Stock then outstanding).

         (c) ADJUSTMENT FOR OTHER DISTRIBUTIONS. If Holdings distributes to all
holders of its Common Stock any of its assets (including but not limited to
cash), debt securities, preferred stock or any rights or warrants to purchase
any such securities, the Exercise Rate shall be adjusted in accordance with the
formula:

          E' = E x   M
                    ---
                    M-F

         where:

         E'  =  the adjusted Exercise Rate.

         E   =  the current Exercise Rate.

         M   =  the Current Market Price per share of Common Stock
                on the record date.

         F   =  the fair market value on the record date of the
                assets, securities, rights or warrants applicable to
                one share of Common Stock. The Board of Directors
                shall determine the fair market value pursuant to
                CLAUSE (N) of SECTION 10 based upon the trading
                prices of publicly traded securities where
                applicable.

         The adjustment shall be made successively whenever any such
distribution is made and shall become effective immediately after the record
date for the determination of stockholders entitled to receive the distribution.

         This clause does not apply to Rights referred to in CLAUSE (B) of this
SECTION 10.

         (d) ADJUSTMENT FOR COMMON STOCK ISSUE. If Holdings issues shares of
Common Stock for a consideration per share less than the Current Market Price
per share on the date Holdings





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<PAGE>   10
fixes the offering price of such additional shares, the Exercise Rate shall be
adjusted in accordance with the formula:


     E' = E  x  O + N
                ------------

                      N x P
                  O + -----
                        M

where:

         E'  =  the adjusted Exercise Rate.

         E   =  the then current Exercise Rate.

         O   =  the number of shares of Common Stock outstanding
                immediately prior to the issuance of such additional
                shares (assuming the conversion, exercise or exchange
                of all Rights and convertible securities into shares
                of Common Stock).

         N   =  the number of additional shares of Common Stock issued.

         P   =  the aggregate consideration received per share for
                the issuance of such additional shares of Common
                Stock.

         M   =  the Current Market Price per share of Common Stock
                on the date of issuance of such additional shares of
                Common Stock.

         The adjustment shall be made successively whenever any such issuance is
made, and shall become effective immediately after such issuance.

         This CLAUSE (D) does not apply to:

                  (1) any of the transactions described in CLAUSES (A), (B), (C)
         or (E) of this SECTION 10 (including transactions referred to in such
         clauses as not being subject thereto),

                  (2) the exercise of Warrants, or the conversion or exchange of
         other securities convertible or exchangeable for Common Stock,

                  (3) Common Stock issued upon the exercise of rights or
         warrants issued to the holders of Common Stock,



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                  (4) Common Stock issued to stockholders of any person that is
         not affiliated with Holdings and that merges into Holdings, or with a
         subsidiary of Holdings, in proportion to their stock holdings of such
         person immediately prior to such merger, upon such merger,

                  (5) Common Stock issued to persons in a bona fide public
         offering pursuant to a firm commitment underwriting, or

                  (6) Common Stock issued to persons who are not affiliates of
         Holdings in a bona fide private placement through a placement agent
         that is a member firm of the NASD (except to the extent that any
         discount from the Current Market Price attributable to restrictions on
         transferability of the Common Stock, as determined in good faith by the
         Board of Directors pursuant to CLAUSE (N) of SECTION 10 and described
         in a Board resolution, shall exceed 5%).

         (e) ADJUSTMENT FOR CONVERTIBLE SECURITIES ISSUE. If Holdings issues any
securities convertible into or exchangeable for Common Stock (other than
securities issued in transactions described in CLAUSES (B) and (C) of this
SECTION 10) for a consideration per share of Common Stock initially deliverable
upon conversion or exchange of such securities less than the Current Market
Price per share on the date of issuance of such securities, the Exercise Rate
shall be adjusted in accordance with the formula:

          E' = E  x O + N
                    -----------

                         N x P
                     O + -----
                          M
where:

         E'  =   the adjusted Exercise Rate.

         E   =   the then current Exercise Rate.

         O   =   the number of shares of Common Stock outstanding
                 immediately prior to the issuance of such securities
                 (assuming the conversion, exercise or exchange of all
                 Rights and convertible securities into shares of
                 Common Stock).

         N   =   the maximum number of shares of Common Stock
                 deliverable upon conversion of or in exchange for
                 such securities at the initial conversion or exchange
                 rate.

         P   =   the aggregate consideration received for the
                 issuance of each such security, plus any additional
                 consideration received upon the exchange or
                 conversion of such security.

         M   =   the Current Market Price per share on the date of
                 issuance of such securities.



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         The adjustment shall be made successively whenever any such issuance is
made, and shall become effective immediately after such issuance.

         If all of the Common Stock deliverable upon conversion or exchange of
such securities has not been issued when such securities are no longer
outstanding, then the Exercise Rate shall promptly be readjusted to the Exercise
Rate which would then be in effect had the adjustment upon the issuance of such
securities been made on the basis of the actual number of shares of Common Stock
issued upon conversion or exchange of such securities.

         This CLAUSE (E) does not apply to:

                  (1) convertible securities issued to stockholders of any
         person that is not affiliated with Holdings and that merges into
         Holdings, or with a subsidiary of Holdings, in proportion to their
         stock holdings of such person immediately prior to such merger, upon
         such merger,

                  (2) convertible securities issued to persons in a bona fide
         public offering pursuant to a firm commitment underwriting,

                  (3) convertible securities issued to persons who are not
         affiliates of Holdings in a bona fide private placement through a
         placement agent which is a member firm of the NASD (except to the
         extent that any discount from the Current Market Price attributable to
         restrictions on transferability of Common Stock issuable upon
         conversion, as determined in good faith by the Board of Directors
         pursuant to CLAUSE (N) of SECTION 10 and described in a Board
         resolution, shall exceed 5%), or

                  (4) convertible securities that are otherwise provided for by
         CLAUSES (A), (B), (C) or (D) of this SECTION 10.

         (f) CURRENT MARKET PRICE. The current market price per share of Common
Stock (the "CURRENT MARKET PRICE") on any date is the average of the Quoted
Prices of the Common Stock for 30 consecutive trading days commencing 45 trading
days before the date in question. The "Quoted Price" of the Common Stock is the
last reported sales price of the Common Stock as reported by NASDAQ National
Market System, or if the Common Stock is listed on a securities exchange, the
last reported sales price of the Common Stock on such exchange which shall be
for





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<PAGE>   13

consolidated trading if applicable to such exchange, or if neither so
reported or listed, the last reported bid price of the Common Stock. In the
absence of one or more such quotations, the Board of Directors of Holdings shall
determine the Current Market Price pursuant to CLAUSE (N) of SECTION 10 in good
faith.

         (g) CONSIDERATION RECEIVED. For purposes of any computation respecting
consideration received pursuant to CLAUSES (D) and (E) of this SECTION 10, the
following shall apply:

                  (1) in the case of the issuance of shares of Common Stock for
         cash, the consideration shall be the amount of such cash, PROVIDED that
         in no case shall any deduction be made for any commissions, discounts
         or other expenses incurred by Holdings for any underwriting of the
         issue or otherwise in connection therewith;

                  (2) in the case of the issuance of shares of Common Stock for
         a consideration in whole or in part other than cash, the consideration
         other than cash shall be deemed to be the fair market value thereof as
         determined in good faith by the Board of Directors pursuant to CLAUSE
         (N) of SECTION 10, based upon the trading prices of publicly traded
         securities where appropriate (irrespective of the accounting treatment
         thereof), and described in a resolution of the Board of Directors of
         Holdings; and

                  (3) in the case of the issuance of securities convertible into
         or exchangeable for shares, the aggregate consideration received
         therefor shall be deemed to be the consideration received by Holdings
         for the issuance of such securities plus the additional minimum
         consideration, if any, to be received by Holdings upon the conversion
         or exchange thereof (the consideration in each case to be determined in
         the same manner as provided in SUBCLAUSES (1) and (2) of this CLAUSE
         (G)).

         (h) WHEN DE MINIMIS ADJUSTMENT MAY BE DEFERRED No adjustment in the
Exercise Rate need be made unless the adjustment would require an increase or
decrease of at least 1% in the Exercise Rate. Any adjustments that are not made
shall be carried forward and taken into account in any subsequent adjustment.

         All calculations under this Section shall be made to the nearest
1/100th of a share.

         (i) WHEN NO ADJUSTMENT REQUIRED. No adjustment need be made for rights
to purchase Common Stock pursuant to a plan by Holdings for reinvestment of
dividends or interest.

         No adjustment need be made for a change in the par value or no par
value of the Common Stock.

         To the extent the Warrants become convertible into cash, no adjustment
need be made thereafter as to the cash. Interest will not accrue on the cash.




                                      -13-
<PAGE>   14

         (j) NOTICE OF ADJUSTMENT. Whenever the Exercise Rate is adjusted,
Holdings shall provide the notices required by SECTION 14 hereof.

         (k) VOLUNTARY INCREASE. Holdings from time to time may increase the
Exercise Rate by any amount for any period of time if the period is at least 20
days and if the increase is irrevocable during the period.

         Whenever the Exercise Rate is increased pursuant to this CLAUSE (K),
Holdings shall mail to Warrant holders a notice of the increase. Holdings shall
mail the notice at least 15 days before the date the increased Exercise Rate
takes effect. The notice shall state the increased Exercise Rate and the period
it will be in effect.

         An increase of the Exercise Rate pursuant to this CLAUSE (K) does not
change or adjust the Exercise Rate otherwise in effect for purposes of CLAUSES
(A), (B), (C), (D) and (E) of this SECTION 10.

         (l) NOTICE OF CERTAIN TRANSACTIONS. If:

                  (1) Holdings takes any action that would require an adjustment
         in the Exercise Rate pursuant to CLAUSES (A), (B), (C), (D) or (E) of
         this SECTION 10;

                  (2) Holdings takes any action that would require a
         supplemental Asset Bridge Warrant Agreement pursuant to CLAUSE (M) of
         this SECTION 10; or

                  (3) there is a liquidation or dissolution of Holdings,

then Holdings shall mail to Warrant holders a notice stating the proposed record
date for a dividend or distribution or the proposed effective date of a
subdivision, combination, reclassification, consolidation, merger, transfer,
lease, liquidation or dissolution. Holdings shall mail the notice at least 15
days before such date. Failure to mail the notice or any defect in it shall not
affect the validity of the transaction.

         (m) REORGANIZATION OF HOLDINGS. If Holdings consolidates or merges with
or into, or transfers or leases all or substantially all its assets to, any
person, upon consummation of such transaction the Warrants shall automatically
become exercisable for the kind and amount of securities, cash or other assets
which the holder of a Warrant would have owned immediately after the
consolidation, merger, transfer or lease if the holder had exercised the Warrant
immediately before the effective date of the transaction. Concurrently with the
consummation of such transaction, the corporation formed by or surviving any
such consolidation or merger if other than Holdings, or the person to which such
sale or conveyance shall have been made, shall enter into a supplemental Asset
Bridge Warrant Agreement so providing and further providing for adjustments
which shall be as nearly equivalent as may be practical to the adjustments






                                      -14-
<PAGE>   15

provided for in this Section. The successor company shall mail to Warrant
holders a notice describing the supplemental Asset Bridge Warrant Agreement.

         If the issuer of securities deliverable upon exercise of Warrants under
the supplemental Asset Bridge Warrant Agreement is an affiliate of the formed,
surviving, transferee or lessee corporation, that issuer shall join in the
supplemental Asset Bridge Warrant Agreement.

         If this CLAUSE (M) applies, CLAUSES (A), (B), (C), (D) and (E) of this
SECTION 10 do not apply.

         (n) HOLDINGS DETERMINATION NOT FINAL. Any determination that Holdings
or its Board of Directors must make pursuant to this Agreement shall be made in
good faith and shall be binding on the holders of Warrants, except as set forth
herein. Holdings shall give each holder of Warrants written notice of any such
determination by Holdings or its Board of Directors. If a majority of the
holders of the Warrants do not agree with any such determination by Holdings or
its Board of Directors, such holders may request, in a notice delivered to
Holdings not later than 30 days after the date on which the holders received
notice of such determination from Holdings, that such determination be made by
an independent investment banking firm (or, if an investment banking firm is
generally not qualified to render such a determination, an independent appraisal
firm) of recognized national standing chosen by Holdings, which determination
shall be final and binding on Holdings and the holders of Warrants, absent
manifest error. All fees and expenses incurred in connection with any
determination made by an independent investment banking firm or appraisal firm,
as the case might be, shall be borne by Holdings, unless such determination is
in agreement with, or more favorable to Holdings than, the determination that
was made by Holdings or its Board of Directors, in which case such fees and
expenses shall be borne by the holders that requested such determination.

         (o) WHEN ISSUANCE OR PAYMENT MAY BE DEFERRED. In any case in which this
SECTION 10 shall require that an adjustment in the Exercise Rate be made
effective as of a record date for a specified event, Holdings may elect to defer
until the occurrence of such event issuing to the holder of any Warrant
exercised after such record date the Warrant Shares and other Capital Stock of
Holdings, if any, issuable upon such exercise over and above the Warrant Shares
and other Capital Stock of Holdings, if any, issuable upon such exercise on the
basis of the Exercise Rate; PROVIDED, HOWEVER, that Holdings shall deliver to
such holder a due bill or other appropriate instrument evidencing such holder's
right to receive such additional Warrant Shares and other Capital Stock of
Holdings upon the occurrence of the event requiring such adjustment.

         (p) FORM OF WARRANTS. Irrespective of any adjustments in the Exercise
Rate or in the kind of shares purchasable upon the exercise of the Warrants,
Warrants theretofore or thereafter issued may continue to express the same price
and kind of shares as are stated in the Warrants initially issuable pursuant to
this Agreement.




                                      -15-
<PAGE>   16

         (q) EXERCISE PRICE. If following any adjustment in the Exercise Rate
pursuant to this SECTION 10, the Exercise Price per share of common stock of
Holdings shall be less than the par value of such common stock, such Exercise
Price per share of common stock shall be increased to the par value of such
stock.

         SECTION 11. NO DILUTION OR IMPAIRMENT: CAPITAL AND OWNERSHIP STRUCTURE.
If any event shall occur as to which the provisions of SECTION 10 are not
strictly applicable but the failure to make any adjustment would adversely
affect the purchase rights represented by the Warrants in accordance with the
essential intent and principles of such Section, then, in each such case,
Holdings shall appoint, at its own expense, an investment banking firm of
recognized national standing that does not have a direct or material indirect
financial interest in Holdings or any of its subsidiaries, who has not been,
and, at the time it is called upon to give independent financial advice to
Holdings, is not (and none of its directors, officers, employees, affiliates or
stockholders are) a promoter, director or officer of Holdings or any of its
subsidiaries, which shall give their opinion upon the adjustment, if any, on a
basis consistent with the essential intent and principles established in SECTION
10, necessary to preserve, without dilution, the purchase rights, represented by
this Agreement and the Warrants. Upon receipt of such opinion, Holdings will
promptly mail a copy thereof to the holders of the Warrants and shall make the
adjustments described therein.

         Holdings will not, by amendment of its certificate of incorporation or
through any consolidation, merger, reorganization, transfer of assets,
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 of the Warrants,
but will at all times in good faith assist in the carrying out of all such terms
and in the taking of all such action as may be necessary or appropriate in order
to protect the rights of the holders of the Warrants against dilution or other
impairment. Without limiting the generality of the foregoing, Holdings (1) will
take all such action as may be necessary or appropriate in order that Holdings
may validly and legally issue fully paid and nonassessable shares of Common
Stock on the exercise of the Warrants from time to time outstanding and (2) will
not take any action which results in any adjustment of the Exercise Rate if the
total number of Warrant Shares issuable after such action upon the exercise of
all of the Warrants would exceed the total number of shares of Common Stock then
authorized by Holdings' certificate of incorporation and available for the
purposes of issue upon such exercise. A consolidation, merger, reorganization or
transfer of assets involving Holdings covered by SECTION 10(M) shall not be
prohibited by or require any adjustment under this SECTION 11.

         SECTION 12. FRACTIONAL INTERESTS. Holdings shall not be required to
issue fractional Warrant Shares on the exercise of Warrants. If more than one
Warrant shall be presented for exercise in full at the same time by the same
holder, the number of full Warrant Shares which shall be issuable upon the
exercise thereof shall be computed on the basis of the aggregate number of
Warrant Shares purchasable on exercise of the Warrants so presented. If any
fraction of a Warrant Share would, except for the provisions of this SECTION 12,
be issuable on the





                                      -16-
<PAGE>   17

exercise of any Warrants (or specified portion thereof), the number of Warrant
Shares which shall be issued by Holdings on exercise of such Warrants shall be
rounded (i) to the last previous whole number if the fraction is less than 0.5
of a Warrant Share or (ii) to the next higher whole number if the fraction is
greater than or equal to 0.5 of a Warrant Share.

         SECTION 13. NOTICES TO WARRANT HOLDERS. Upon any adjustment of the
Exercise Rate pursuant to SECTION 10, Holdings shall promptly thereafter cause
to be delivered, by first-class mail, postage prepaid, to each of the registered
holders of the Warrant Certificates at such holder's address appearing on the
Warrant Register a certificate of an Officer of Holdings setting forth the
Exercise Rate after such adjustment and setting forth in reasonable detail the
method of calculation and the facts upon which such calculations are based and
setting forth the number of Warrant Shares (or portion thereof) issuable after
such adjustment in the Exercise Rate, upon exercise of a Warrant and payment of
the Exercise Price. Where appropriate, such notice shall be given in advance and
included as a part of the notice required to be mailed under the other
provisions of this SECTION 13.

         In case:

                  (a) Holdings shall authorize the issuance to all holders of
         shares of Common Stock of rights, options or warrants to subscribe for
         or purchase shares of Common Stock or of any other subscription rights
         or warrants;

                  (b) Holdings shall authorize the distribution to all holders
         of shares of Common Stock of evidences of its indebtedness or assets
         (other than cash dividends or cash distributions payable out of
         consolidated earnings or earned surplus or dividends payable in shares
         of Common Stock or distributions referred to in CLAUSE (A) of SECTION
         10 hereof);

                  (c) of any consolidation or merger to which Holdings is a
         party and for which approval of any stockholders of Holdings is
         required, or of the conveyance or transfer of the properties and assets
         of Holdings substantially as an entirety, or of any reclassification or
         change of Common Stock issuable upon exercise of the Warrants (other
         than a change in par value, or from par value to no par value, or from
         no par value to par value, or as a result of a subdivision or
         combination), or a tender offer or exchange offer for shares of Common
         Stock;

                  (d) of the voluntary or involuntary dissolution, liquidation
         or winding up of Holdings; or

                  (e) Holdings proposes to take any action which would require
         an adjustment of the Exercise Rate pursuant to SECTION 10;



                                      -17-
<PAGE>   18

then Holdings shall cause to be given to each of the registered holders of the
Warrant Certificates at such holder's address appearing on the Warrant Register,
at least 20 days (or 10 days in any case specified in clauses (a) or (b) above)
prior to the applicable record date hereinafter specified, or promptly in the
case of events for which there is no record date, by first-class mail, postage
prepaid, a written notice stating (i) the date as of which any such subdivision,
combination or reclassification is to be made, or (ii) the date as of which the
holders of record of shares of Common Stock to be entitled to receive any such
dividends, rights, options, warrants or distribution are to be determined, or
(iii) the initial expiration date set forth in any tender offer or exchange
offer for shares of Common Stock, or (iv) the date on which any such
consolidation, merger, conveyance, transfer dissolution, liquidation or winding
up is expected to become effective or consummated, and the date as of which it
is expected that holders of record of shares of Common Stock shall be entitled
to exchange such shares for securities or other property, if any, deliverable
upon such reclassification, consolidation, merger, conveyance, transfer,
dissolution, liquidation or winding up. The failure to give the notice required
by this SECTION 13 or any delay therein shall not affect the legality or
validity of any distribution, right, option, warrant, consolidation, merger,
conveyance, transfer, dissolution, liquidation or winding up, or the vote upon
any action.

         Nothing contained in this Agreement or in any of the Warrant
Certificates shall be construed as conferring upon the holders thereof the right
to vote or to consent or to receive notice as stockholders in respect of the
meetings of stockholders or the election of Directors of Holdings or any other
matter, or any rights whatsoever as stockholders of Holdings; PROVIDED, that
each registered holder of Warrants shall be entitled to receive all notices sent
generally to stockholders, such notices to be delivered pursuant to SECTION 14
hereof at the address of such holder appearing on the Warrant Register.

         SECTION 14. NOTICES. Any notice or demand authorized by this Agreement
to be given or made by the registered holder of any Warrant Certificate to or on
Holdings shall be delivered or sent by registered, certified or express mail,
postage prepaid, return receipt requested, or given or made by facsimile, in
each case, at the address specified below Holdings' name on the signature page
to the Asset Bridge Securities Purchase Agreement, or at such other address as
shall be designated by Holdings in a written notice to the Warrant holders.
Except as otherwise provided in this Agreement, all such communications shall be
deemed to have been duly given when transmitted by facsimile (and electronic
confirmation thereof has been received) or personally delivered or, in the case
of a mailed notice, upon receipt, in each case given or addressed as aforesaid.

         Any notice pursuant to this Agreement to be given by Holdings to the
registered holder(s) of any Warrant Certificate shall be delivered or sent by
registered, certified or express mail, postage prepaid, return receipt
requested, or given or made by facsimile (and electronic confirmation thereof
has been received), in each case, at the address of such holder appearing on the
Warrant Register, or at such other address as shall be designated by such holder
in a written





                                      -18-
<PAGE>   19

notice to Holdings. Except as otherwise provided in this Agreement, all such
communications shall be deemed to have been duly given when transmitted by
facsimile or personally delivered or in the case of a mailed notice, upon
receipt, in each case given or addressed as aforesaid.

         SECTION 15. SUPPLEMENTS AND AMENDMENTS. The provisions of this
Agreement, including the provisions of this sentence, may not be amended,
modified or supplemented, and waivers or consents to departures from the
provisions of this Agreement may not be given unless Holdings has obtained the
written consent of holders of at least a majority of the outstanding Warrant
Certificates.

         SECTION 16. SUCCESSORS. All the covenants and provisions of this
Agreement by or for the benefit of Holdings shall bind and inure to the benefit
of its respective successors and assigns hereunder.

         SECTION 17. TERMINATION. This Agreement shall terminate when all
Warrants have been exercised.

         SECTION 18. NEW YORK LAW, SUBMISSION TO JURISDICTION, WAIVER OF JURY
TRIAL. THIS AGREEMENT AND EACH WARRANT CERTIFICATE SHALL BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF NEW YORK. EACH PARTY
HERETO HEREBY SUBMITS TO THE NONEXCLUSIVE JURISDICTION OF THE UNITED STATES
DISTRICT COURT FOR THE SOUTHERN DISTRICT OF NEW YORK AND OF ANY NEW YORK STATE
COURT SITTING IN NEW YORK CITY FOR PURPOSES OF ALL LEGAL PROCEEDINGS ARISING OUT
OF OR RELATING TO THIS ASSET BRIDGE WARRANT AGREEMENT OR THE TRANSACTIONS
CONTEMPLATED HEREBY. EACH PARTY HERETO IRREVOCABLY WAIVES, TO THE FULLEST EXTENT
PERMITTED BY LAW, ANY OBJECTION WHICH IT MAY NOW OR HEREAFTER HAVE TO THE LAYING
OF THE VENUE OF ANY SUCH PROCEEDING BROUGHT IN SUCH A COURT AND ANY CLAIM THAT
ANY SUCH PROCEEDING BROUGHT IN SUCH A COURT HAS BEEN BROUGHT IN AN INCONVENIENT
FORUM. EACH PARTY HERETO IRREVOCABLY WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY
IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO THIS ASSET BRIDGE WARRANT
AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

         SECTION 19. BENEFITS OF THIS AGREEMENT. Except as expressly set forth
herein, nothing in this Agreement shall be construed to give to any person or
corporation other than Holdings and the registered holders of the Warrant
Certificates any legal or equitable right, remedy or claim under this Agreement;
but, except as so set forth, this Agreement shall be for the sole and exclusive
benefit of Holdings and the registered holders of the Warrant Certificates.





                                      -19-
<PAGE>   20

         SECTION 20. COUNTERPARTS. This Agreement may be executed in any number
of counterparts and each of such counterparts shall for all purposes be deemed
to be an original, and all such counterparts shall together constitute but one
and the same instrument.






                                      -20-
<PAGE>   21



         IN WITNESS WHEREOF, the parties hereto have caused this Asset Bridge
Warrant Agreement to be duly executed, as of the day and year first above
written.

                                         RAILAMERICA, INC.


                                         By:
                                            ----------------------------------
                                              Name:
                                              Title:



                                         PURCHASERS:
                                         RAIL AMERICA HOLDINGS FUNDING,
                                         INC.


                                         By:
                                            ----------------------------------
                                              Name:  Eugene F. Martin
                                              Title:  Senior Vice President






                                      -21-
<PAGE>   22



                                                                       EXHIBIT A
                          [Form of Warrant Certificate]

                                     [Face]

         THE SECURITIES EVIDENCED OR CONSTITUTED HEREBY HAVE BEEN ACQUIRED FOR
         INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
         1933, AS AMENDED. SUCH SECURITIES MAY NOT BE SOLD, TRANSFERRED, PLEDGED
         OR HYPOTHECATED UNLESS THE REGISTRATION PROVISIONS OF SAID ACT AND ANY
         APPLICABLE STATE SECURITIES LAWS HAVE BEEN COMPLIED WITH OR UNLESS
         HOLDINGS HAS RECEIVED AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO
         HOLDINGS THAT SUCH REGISTRATION IS NOT REQUIRED.

No. ____

                               Warrant Certificate

                                RAILAMERICA, INC.

         This Warrant Certificate certifies that __________________, or its
registered assigns, is the registered holder of Warrants (the "WARRANTS") to
purchase Common Stock, $0.001 par value per share (the "COMMON STOCK"), of
RailAmerica, Inc., a Delaware corporation ("HOLDINGS"). This Warrant entitles
the holder upon exercise to receive from Holdings, up to [_______]1 fully paid
and nonassessable shares of Common Stock (each, a "WARRANT SHARE") at an
exercise price equal to the closing price per share of Common Stock of Holdings
traded on the NASDAQ National Market System at the close of trading on the
Issuance Date (the "EXERCISE PRICE") payable in lawful money of the United
States of America upon surrender of this Warrant Certificate and payment of the
Exercise Price at the office or agency of Holdings designated for such purpose,
but only subject to the conditions set forth herein and in the Asset Bridge
Warrant Agreement referred to on the reverse hereof. The number of Warrant
Shares issuable upon exercise of the Warrants are subject to adjustment upon the
occurrence of certain events set forth in the Asset Bridge Warrant Agreement.

         No Warrant may be exercised after 5:00 p.m., New York City time, on the
seventh anniversary of the date upon which the such Warrant was released from
escrow (the "EXERCISE DATE") pursuant to the terms of the Asset Bridge Escrow
Agreement, dated as of February 4, 2000 (as amended, supplemented or otherwise
modified, the "ESCROW AGREEMENT"), among Holdings, the Purchasers parties
thereto and Snoga, Inc., as escrow agent.

         Reference is hereby made to the further provisions of this Warrant
Certificate set forth on the reverse hereof and such further provisions shall
for all purposes have the same effect as though fully set forth at this place.

--------

1 Represents 3.5% of the fully-diluted Capital Stock of Holdings on the
  closing date.



                                       A-1


<PAGE>   23



         THIS WARRANT CERTIFICATE SHALL BE GOVERNED AND CONSTRUED IN ACCORDANCE
WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF
CONFLICTS OF LAWS.

         IN WITNESS WHEREOF, Holdings has caused this Warrant Certificate to be
signed by an officer.

         Dated: _____________


                                       RAILAMERICA, INC.




                                       By:
                                          ----------------------------------
                                              Name:
                                              Title:





                                       A-2


<PAGE>   24



                          [Form of Warrant Certificate]

                                    [Reverse]

         The Warrants evidenced by this Warrant Certificate are part of a duly
authorized issue of Warrants expiring on the seventh anniversary of such
Warrants' Exercise Date entitling the holder on exercise to receive shares of
Common Stock, $0.001 par value per share, of Holdings (the "COMMON STOCK"), and
are issued or to be issued pursuant to an Asset Bridge Warrant Agreement dated
as of February 4, 2000 (as amended, supplemented or otherwise modified, the
"ASSET BRIDGE WARRANT AGREEMENT") among Holdings and the Purchasers parties
thereto, which Asset Bridge Warrant Agreement is hereby incorporated by
reference in and made a part of this instrument and is hereby referred to for a
description of the rights, limitation of rights, obligations, duties and
immunities thereunder of Holdings and the holders (the words "holders" or
"holder" meaning the registered holders or registered holder) of the Warrants. A
copy of the Asset Bridge Warrant Agreement may be obtained by the holder hereof
upon written request to Holdings.

         A Warrant will not be exercisable until its respective Exercise Date.
The holder of Warrants evidenced by this Warrant Certificate may exercise them
by surrendering this Warrant Certificate, with the form of election to purchase
set forth hereon properly completed and executed, together with payment of the
Exercise Price in cash at the office of Holdings designated for such purpose. In
the event that upon any exercise of Warrants evidenced hereby the number of
Warrants exercised shall be less than the total number of Warrants evidenced
hereby, there shall be issued to the holder hereof or his assignee a new Warrant
Certificate evidencing the number of Warrants not exercised. No adjustment shall
be made for any dividends on any Common Stock issuable upon exercise of this
Warrant.

         The Asset Bridge Warrant Agreement provides that upon the occurrence of
certain events the number of Warrant Shares issuable upon the exercise of each
Warrant (the "EXERCISE RATE") may, subject to certain conditions, be adjusted.
If the Exercise Rate is adjusted, the Asset Bridge Warrant Agreement provides
that the number of shares of Common Stock issuable upon the exercise of each
Warrant shall be adjusted. No fractions of a share of Common Stock will be
issued upon the exercise of any Warrant.

         Warrant Certificates, when surrendered at the office of Holdings by the
registered holder thereof in person or by legal representative or attorney duly
authorized in writing, may be exchanged, in the manner and subject to the
limitations provided in the Asset Bridge Warrant Agreement, but without payment
of any service charge, for another Warrant Certificate or Warrant Certificates
of like tenor evidencing in the aggregate a like number of Warrants.

         Upon due presentation for registration of transfer of this Warrant
Certificate at the office of Holdings, a new Warrant Certificate or Warrant
Certificates of like tenor and evidencing in the aggregate a like number of
Warrants shall be issued to the transferee(s) in exchange for this Warrant
Certificate, subject to the limitations provided in the Asset Bridge Warrant
Agreement, without charge except for any tax or other governmental charge
imposed in connection therewith.



                                       A-3


<PAGE>   25




         Holdings may deem and treat the registered holder(s) thereof as the
absolute owner(s) of this Warrant Certificate (notwithstanding any notation of
ownership or other writing hereon made by anyone), for the purpose of any
exercise hereof of any distribution to the holder(s) hereof, and for all other
purposes, and Holdings shall not be affected by any notice to the contrary.
Neither the Warrants nor this Warrant Certificate entitles any holder hereof to
any rights of a stockholder of Holdings.






                                       A-4


<PAGE>   26



                         [Form of Election to Purchase]

                    (To Be Executed Upon Exercise Of Warrant)

         The undersigned hereby irrevocably elects to exercise the right,
represented by this Warrant Certificate, to receive ______________ shares of
Common Stock and herewith tenders payment for such shares to the order of
RailAmerica, Inc., a Delaware corporation, in the amount of 2$___ per share in
accordance with the terms hereof. The undersigned requests that a certificate
for such shares be registered in the name of ______________ ([SS#______________]
[Taxpayer ID#______________]), whose address is ______________ and that such
shares be delivered to ______________ whose address is ______________. If said
number of shares is less than all of the shares of Common Stock purchasable
hereunder, the undersigned requests that a new Warrant Certificate representing
the remaining balance of such shares be registered in the name of
______________, whose address is ______________, and that such Warrant
Certificate be delivered to ______________, whose address is
_______________________________.



                                            Signature:
                                                      --------------------------

Date:
     --------------------------



Signature Guaranteed:
                     --------------------------



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

2 Insert in an amount equal to the closing price per share of Common
  Stock of Holdings traded on the NASDAQ National Market System at the
  close of trading on the Issuance Date




                                       A-5