EXHIBIT 3.5a

                             ARTICLES OF AMENDMENT
                                      OF
                      INTERSTATE POWER AND LIGHT COMPANY

    (Regarding Designation and Authorization of 8.375% Series A Cumulative
        Preferred Stock and 8.375% Series B Cumulative Preferred Stock)

TO THE SECRETARY OF STATE
OF THE STATE OF IOWA:

           Pursuant  to  Section  602 of the  Iowa  Business  Corporation  Act,
Interstate Power and Light Company,  an Iowa  corporation (the  "Corporation"),
adopts the following  amendment  regarding the designation and authorization of
8.375%  Series A  Cumulative  Preferred  Stock and 8.375%  Series B  Cumulative
Preferred Stock by the Corporation.

1.    The name of the Corporation is Interstate Power and Light Company.

2.    The  preferences,  limitations,  relative  rights and other  terms of the
      8.375%  Series A  Cumulative  Preferred  Stock  and the  8.375%  Series B
      Cumulative  Preferred  Stock were  determined  by Erroll B.  Davis,  Jr.,
      Chairman  and Chief  Executive  Officer of the  Corporation  (the "Senior
      Executive  Officer"),  pursuant  to  authority  granted  by the  Board of
      Directors of the  Corporation  under  Section  490.825(5)(h)  of the Iowa
      Business  Corporation  Act on November  20, 2002. A true and correct copy
      of the  portion  of the  consent  action  by which the  Senior  Executive
      Officer  authorized  the 8.375% Series A Cumulative  Preferred  Stock and
      the  8.375%  Series B  Cumulative  Preferred  Stock  and  determined  the
      respective  preferences,  limitations,  relative  rights and other  terms
      thereof is attached hereto as Exhibit A and  incorporated  herein by this
      reference.

3.    The  consent  action  of the  Senior  Executive  Officer  as set forth in
      Exhibit A was duly adopted by such Senior  Executive  Officer on December
      18, 2002  pursuant to authority  granted by the Board of Directors of the
      Corporation under Section  490.825(5)(h) of the Iowa Business Corporation
      Act on November 20, 2002.



Dated:  December 18, 2002

                                    INTERSTATE POWER AND
                                    LIGHT COMPANY



                                    By:  /s/ Erroll B. Davis, Jr.
                                         ------------------------------------
                                         Chairman and Chief Executive Officer


<PAGE>

                  CONSENT ACTION OF SENIOR EXECUTIVE OFFICER
            ESTABLISHING 8.375% SERIES A CUMULATIVE PREFERRED STOCK
                AND 8.375% SERIES B CUMULATIVE PREFERRED STOCK

           There is hereby  authorized  and  established  a series of shares of
Preferred  Stock,  $.01 par value, of the Company to be known and designated as
the  8.375%  Series  A  Cumulative   Preferred  Stock,  with  the  preferences,
limitations,  relative  rights  and other  terms as set forth  below.  There is
also hereby  authorized and established a series of shares of Preferred  Stock,
$.01 par  value,  of the  Company  to be known  and  designated  as the  8.375%
Series  B  Cumulative  Preferred  Stock,  with  the  preferences,  limitations,
relative rights and other terms as set forth below.


                          CERTIFICATE OF DESIGNATION

                  8.375% Series A Cumulative Preferred Stock

Section 1. Designation and Number.
           -----------------------

(a)   There is hereby  created out of the  authorized  but  unissued  Preferred
Stock a series of Preferred  Stock  designated as "8.375%  Series A  Cumulative
Preferred  Stock"  (the  "Series A  Preferred  Stock").  The  number  of shares
constituting the Series A Preferred Stock shall be 6,000,000.

(b)   All  shares  of  the  Series A   Preferred  Stock  redeemed,   purchased,
exchanged,  converted  or  otherwise  acquired  by  the  Corporation  shall  be
retired  and  canceled  and,  upon  the  taking  of  any  action   required  by
applicable  law,  shall be restored to the status of  authorized  but  unissued
shares  of  Preferred  Stock,   without  designation  as  to  series,  and  may
thereafter  be  designated  or  redesignated  and issued or reissued as part of
any  series  of  Preferred  Stock.  At  such  time  as no  shares  of  Series A
Preferred  Stock are  issued and  outstanding  as a result of the  issuance  of
shares  of  Series B  Preferred  Stock  in  exchange  for  shares  of  Series A
Preferred  Stock pursuant to the Exchange Offer,  the  appropriate  officers of
the  Corporation  shall  promptly  cause to be prepared and duly filed with the
Secretary  of State of the State of Iowa such  documents  as are  necessary  to
restate the Restated  Articles of  Incorporation  to  eliminate  the Sections 1
through 8 establishing the Series A Preferred Stock.

(c)   Capitalized  terms used herein and not otherwise defined herein or in the
Corporation's  Restated  Articles of Incorporation  shall have the meanings set
forth in Section 7.

Section 2. Ranking.
           --------

(a)   The  Series A  Preferred  Stock  shall rank,  with  respect to payment of
dividends and distribution of assets upon  liquidation,  dissolution or winding
up of the Corporation:

          (i) senior to Junior Stock; and

          (ii) on a parity with Parity Stock.

Section 3. Dividends.
           ----------

(a)   The holders of shares of the Series A  Preferred  Stock shall be entitled
to receive,  when,  as and if declared by the Board of  Directors  out of funds
legally  available  for the payment of dividends,  cash  dividends at an annual
rate of 8.375% of the Liquidation Preference (the "Original Rate").

(b)   In the event that a Registration  Default  occurs,  the rate of dividends
that accrues on the Series A  Preferred  Stock shall be increased  ("Additional
Dividend  Payments") by 0.25% per annum upon the  occurrence of a  Registration
Default,  which rate shall increase by an additional  0.25% at the beginning of
each subsequent  90-day period that such Additional  Dividend Payments continue
to accrue  under any such  circumstance,  provided  that the maximum  aggregate
increase  in the  dividend  accrual  rate  shall in no event  exceed  1.25% per
annum.  Following  the  cure  of  all  Registration  Defaults  the  accrual  of
Additional  Dividend  Payments shall cease and the dividend  accrual rate shall
revert to the Original Rate.

<PAGE>

(c)   If the Shelf  Registration  Statement  (if  required)  is unusable by the
holders  of the  Series A  Preferred  Stock  for any  reason  after  the  Shelf
Registration  Statement  has  been  declared  effective  by the  SEC,  and  the
aggregate number of days in any consecutive  twelve-month  period for which the
Shelf  Registration  Statement  shall  not be  usable  exceeds  30  days in the
aggregate,  then the rate of dividend  payments  that  accrues on the  Series A
Preferred  Stock,  so long as any  shares  of  Series  A  Preferred  Stock  are
Registrable  Securities,  shall be  increased  by 0.25% per annum for the first
90-day  period (or portion  thereof)  beginning on the 31st day  following  the
date that such Shelf  Registration  Statement  ceases to be usable,  which rate
shall be increased by an  additional  0.25% per annum at the  beginning of each
subsequent 90-day period,  provided that the maximum aggregate  increase in the
dividend  accrual rate shall in no event  exceed  1.25% per annum.  Any amounts
payable  under  this  Section 3(c)  shall also be deemed  "Additional  Dividend
Payments." Upon the Shelf  Registration  Statement once again becoming  usable,
the rate of dividend  payments  that  accrues on the Series A  Preferred  Stock
shall be  reduced to the  Original  Rate if the  Corporation  is  otherwise  in
compliance  with the  Registration  Rights  Agreement at such time.  Additional
Dividend  Payments  shall  be  computed  based  on the  actual  number  of days
elapsed in each  90-day  period in which the Shelf  Registration  Statement  is
unusable.

(d)   The  Corporation   shall  notify  each  record  holder  of  the  Series A
Preferred  Stock within three  Business Days after each and every date on which
an event occurs in respect of which Additional  Dividend  Payments are required
to be paid (an "Event  Date").  The Additional  Dividend  Payments due shall be
payable on each  dividend  payment date with respect to the Series A  Preferred
Stock as set forth in  Section 3(e)  and on the same terms and  conditions  and
subject to the same  limitations  as  pertain  at such time for the  payment of
regular  dividends.  Each obligation to pay Additional  Dividend Payments shall
be deemed to accrue and be  cumulative  from and  including  the day  following
the applicable Event Date.

(e)   All  dividends on the  Series A  Preferred  Stock (other than  Additional
Dividends)  shall accrue and be cumulative from the date of original  issuance.
Dividends  shall  be  payable  quarterly  in  arrears  on  March  15,  June 15,
September 15  and  December 15  of each year,  beginning on March 15,  2003. If
any of those dates is not a Business  Day, then  dividends  shall be payable on
the next  succeeding  Business Day.  Dividends  shall be payable on those dates
to holders  of record as they  appear in the stock  records of the  Corporation
at the close of  business on the  applicable  record  date,  which shall be the
last  Business  Day of the month  prior to the  month in which  the  applicable
dividend  payment date falls.  The amount of dividends  payable for the initial
dividend  period or any period  shorter  than a full  dividend  period shall be
computed on the basis of a 360-day  year  consisting  of twelve  30-day  months
and the actual number of days elapsed in the period.

(f)   The Board of Directors  shall not authorize,  and the  Corporation  shall
not pay, any dividends on the Series A  Preferred  Stock or set aside funds for
the payment of dividends if the terms of any of the  Corporation's  agreements,
including  agreements  relating to indebtedness,  prohibit that  authorization,
payment or setting  aside of funds or provide that the  authorization,  payment
or setting  aside of funds is a breach of or a default  under  that  agreement,
or if the  authorization,  payment or setting  aside of funds is  restricted or
prohibited by law.

(g)   Notwithstanding   the  provisions  of  Section 3(f),   dividends  on  the
Series A  Preferred  Stock  shall  accrue  whether or not the  Corporation  has
earnings,  whether or not there are funds legally  available for the payment of
dividends  and whether or not dividends are  authorized.  No interest  shall be
paid in respect of any accrued but unpaid  dividends on the Series A  Preferred
Stock.

(h)   Holders of shares of the Series A  Preferred  Stock shall not be entitled
to any  dividends  in  excess  of full  cumulative  dividends  on the  Series A
Preferred Stock as described  above.  Any dividend payment made on the Series A
Preferred  Stock  shall  first be credited  against  the  earliest  accrued and
unpaid dividend due.

(i)   The Corporation  shall not pay any dividends with respect to Junior Stock
if dividends payable on the Series A Preferred Stock are in arrears.

Section 4. Liquidation Preference.
           -----------------------

(a)   Upon any voluntary or involuntary liquidation,  dissolution or winding up
of the  Corporation,  each  holder of shares of the  Series A  Preferred  Stock
shall be entitled to payment,  out of the  Corporation's  assets  available for
distribution  to  its  shareowners,  of an  amount  equal  to  the  Liquidation
Preference  plus an amount  equal to all accrued and unpaid  dividends on those
shares to, but excluding,  the date of  liquidation,  dissolution or winding up
before any  distribution is made on any Junior Stock.  After payment in full of

<PAGE>

the  Liquidation  Preference  and the amount  equal to all  accrued  and unpaid
dividends  to which  holders  of shares  of the  Series A  Preferred  Stock are
entitled,  the holders of the  Series A  Preferred  Stock shall not be entitled
to any further  participation in any distribution of the Corporation's  assets.
If upon any voluntary or  involuntary  liquidation,  dissolution  or winding up
of  the  Corporation,  the  amounts  payable  with  respect  to  shares  of the
Series A  Preferred  Stock and any Parity Stock are not paid in full,  then the
holders  of shares of the  Series A  Preferred  Stock  and the  holders  of the
Parity  Stock  shall  share  equally  and  ratably in any  distribution  of the
Corporation's  assets in proportion to the full distributable  amounts to which
each such holder is entitled.

(b)   Neither the voluntary sale,  conveyance,  exchange or transfer, for cash,
shares of stock,  securities or other  consideration,  of all or  substantially
all of the Corporation's  property or assets nor the  consolidation,  merger or
amalgamation  of  the  Corporation  with  or  into  any  other  entity  or  the
consolidation,  merger or  amalgamation  of any other  entity  with or into the
Corporation  will be  deemed  to be a  voluntary  or  involuntary  liquidation,
dissolution or winding up of the Corporation.

Section 5. Redemption.
           -----------

(a)   The  Corporation  may not redeem the  Series A  Preferred  Stock prior to
March 15,  2013.  On or after  March 15,  2013,  the  Corporation,  at its sole
option,  may  redeem  the  Series A  Preferred  Stock,  out  of  funds  legally
available  therefor,  in whole or in part  from  time to time at a price of $25
per  share,  plus an amount  equal to  accrued  and  unpaid  dividends  to, but
excluding, the redemption date (the "Redemption Price").

(b)   In the case of any partial  redemption,  the  Corporation  may select the
shares of the Series A  Preferred  Stock to be redeemed on a pro rata basis, by
lot or any other method that the  Corporation,  in its  discretion,  deems fair
and   appropriate.   However,   the   Corporation   may,   without   regard  to
proportionality  or any other factor,  redeem all of the shares of the Series A
Preferred  Stock held by any  holders of fewer than 100 shares of the  Series A
Preferred  Stock (or all the  shares of the  Series A  Preferred  Stock held by
holders who would hold fewer than 100 shares of the  Series A  Preferred  Stock
as a result of such redemption).

(c)   If the Corporation  elects to redeem the Series A  Preferred Stock in the
manner  described  in this  Section 5,  then  notice  of such  redemption  (the
"Redemption  Notice")  shall be given to the holders of record of shares of the
Series A  Preferred  Stock not less than 45 nor more  than 90 days  before  the
date of the redemption (the  "Redemption  Date");  provided,  however,  that no
failure  to give such  Redemption  Notice on or any  deficiency  therein  shall
affect the validity of the  procedure  for the  redemption of any shares of the
Series A  Preferred  Stock to be redeemed except as to the holder or holders to
whom the  Corporation  has failed to give said  Redemption  Notice or except as
to the holder or  holders  whose  Redemption  Notice  was  defective.  All such
Redemption Notices shall state:

          (i) the Redemption Date;

          (ii) the Redemption Price;

          (iii) the total number of shares of the Series A Preferred Stock to be
     redeemed;

          (iv) that the  Redemption  Price will  become  due and  payable on the
     Redemption  Date upon each such  share of  Series A  Preferred  Stock to be
     redeemed and that  dividends  thereon will cease to accrue on and after the
     Redemption Date; and

          (v) the place or places where  certificates for the Series A Preferred
     Stock are to be surrendered for payment of the Redemption Price.

(d)   Prior to any  Redemption  Date,  the  Corporation  shall  deposit  with a
designated  bank or trust  company as paying agent (or, if the  Transfer  Agent
or the  Corporation  is  acting  as the  paying  agent,  segregate  and hold in
trust) an amount of  consideration  sufficient to pay the  Redemption  Price of
all shares of  Series A  Preferred  Stock which are to be redeemed on that date
other than any  Series A  Preferred  Stock called for prior to the date of such
deposit.

(e)   Notice  of  redemption   having  been  given  as  described   above,  the
Redemption  Price of the Series A  Preferred Stock to be redeemed shall, on the
Redemption Date,  become due and payable,  and from and after such date (unless

<PAGE>

the  Corporation  shall default in the payment of the Redemption  Price),  such
shares of Series A  Preferred Stock shall no longer be  outstanding,  dividends
on such  Series A  Preferred  Stock  shall  cease to accrue  and all  rights of
holders  thereof  as  shareowners  of the  Corporation  (except  the  right  to
receive the Redemption  Price without  interest)  shall cease.  Upon book-entry
transfer  or  surrender  of any  certificate  representing  any  such  share of
Series A  Preferred Stock for redemption in accordance  with said notice,  such
Redemption Price shall thereupon be paid.

(f)   If any  certificate  that  represents  more  than one  share of  Series A
Preferred  Stock,  not all of which are subject to  redemption,  is surrendered
at any office or agency of the  Corporation  designated for that purpose (with,
if the  Corporation or the Transfer Agent so requires,  due  endorsement by, or
a written  instrument of transfer in form  satisfactory  to the Corporation and
the  Transfer  Agent duly  executed  by, the  holder  thereof or such  holder's
attorney duly authorized in writing),  the Corporation  shall execute,  and the
Transfer  Agent  shall  deliver  to the  holder  of  such  shares  of  Series A
Preferred  Stock without service  charge,  a new  certificate or  certificates,
representing  any number of shares of Series A  Preferred  Stock,  as requested
by such  holder,  in an  aggregate  amount  equal to the  number of shares  not
redeemed and represented by the certificate so surrendered.

(g)   Payment  of the  Redemption  Price for the  Series A  Preferred  Stock is
conditioned upon book-entry  transfer or physical  delivery of the certificates
representing   the  Series A   Preferred   Stock,   together   with   necessary
endorsements  to  the  Transfer  Agent  at  any  time  after  delivery  of  the
Redemption  Notice.  Payment of the Redemption Price for the Series A Preferred
Stock will be made  promptly  following  the later of the  Redemption  Date and
the time of  book-entry  transfer  or  physical  delivery  of the  certificates
representing the Series A Preferred Stock subject to redemption.

(h)   If the Transfer Agent holds money  sufficient to pay the Redemption Price
of the Series A  Preferred  Stock on the Redemption Date in accordance with the
terms of this Section 5,  then, on the Redemption Date, the Series A  Preferred
Stock  will cease to be  outstanding,  whether or not  book-entry  transfer  is
made or certificates  representing  the Series A  Preferred Stock are delivered
to the  Transfer  Agent.  At such  time,  all rights of a holder as a holder of
Series A  Preferred Stock shall terminate,  other than the right to receive the
Redemption Price.

(i)   If the  Redemption  Date falls after a dividend  payment  record date and
before the related  dividend  payment  date,  then the holders of the shares of
Series A  Preferred  Stock at the close of  business on that  dividend  payment
record date will be entitled to receive the  dividend  payable of those  shares
on the  corresponding  dividend  payment date.  However,  the Redemption  Price
payable on such  Redemption  Date will not include  dividends  accruing on that
dividend  payment  record  date  and  payable  on  the  corresponding  dividend
payment date.

Section 6. Voting Rights.
           --------------

(a)   The  shares of  Series A  Preferred  Stock  shall  have no voting  rights
except as set forth in this Section 6 or as otherwise provided by Iowa law.

(b)   In the  event  that  any four  quarterly  cumulative  dividends,  whether
consecutive  or not,  payable on the Series A  Preferred  Stock are in arrears,
the  holders of the  Series A  Preferred  Stock  shall  have the right,  voting
separately  as a class  together  with  holders of any Parity  Stock upon which
like  voting  rights  have  been  conferred  and are  exercisable,  at the next
meeting of  shareowners  called for the  election  of  directors,  to elect two
members of the Board of  Directors.  The right of such  holders of the Series A
Preferred  Stock to elect  members  of the Board of  Directors  shall  continue
until such time as all dividends  accumulated  and in arrears on such shares of
the Series A  Preferred  Stock have been paid in full, at which time such right
will  terminate,   subject  to  revesting  in  the  event  of  each  and  every
subsequent  failure to pay dividends as described  above.  Upon any termination
of the  right  of the  holders  of the  Series A  Preferred  Stock to vote as a
class  for  directors,  the term of  office  of all  directors  then in  office
elected by such holders voting as a class will terminate immediately.

(c)   Without  the  affirmative  vote or  consent  of the  holders  of at least
two-thirds of the outstanding  shares of the Series A  Preferred Stock,  voting
as a single  class,  or voting as a single class  together  with holders of any
other  series of Preferred  Stock (i) upon which like voting or consent  rights
have been  conferred and (ii) which are similarly  affected by the matter to be
voted upon, the Corporation shall not:

<PAGE>

          (i) increase the amount of authorized shares of the Preferred Stock or
     create or issue  any  class of stock in  addition  to the  Preferred  Stock
     ranking  senior to or on a parity with the Preferred  Stock,  or any series
     thereof, as to the payment of dividends or the distribution of assets;

          (ii) adopt any amendment to the Restated  Articles of Incorporation of
     the Corporation that adversely alters the preferences, powers and rights of
     the Series A Preferred Stock (provided, that Articles of Amendment to issue
     a series of Preferred  Stock shall not be considered to adversely alter the
     preferences,  powers  and  rights of the Series A  Preferred  Stock  solely
     because  such series is on parity  with the Series A  Preferred  Stock with
     respect to payment of dividends and distribution of assets);

          (iii)  issue  any  shares  of  Preferred  Stock of any  series  if the
     cumulative  dividends  payable  on  the  Series A  Preferred  Stock  are in
     arrears; or

          (iv) create or issue any shares of Preferred  Stock of any series that
     rank senior to the Series A  Preferred  Stock as to payment of dividends or
     the distribution of assets.

(d)   On any  matter set forth in  Section 6(b)  or  Section 6(c)  in which the
holders of the Series A  Preferred Stock are entitled to vote as a class,  such
holders  will be entitled to one vote per share.  On any other matter for which
holders  of the  Series A  Preferred  Stock  are  provided  the  right  to vote
together  with holders of the Common  Stock under Iowa law, if any,  holders of
the  Series A  Preferred  Stock  will be  entitled  to the  number of votes per
share determined by dividing the Liquidation Preference of such share by 100.

Section 7. Certain Definitions.  As used in this Amendment, the following
           --------------------
terms shall have the following meanings, unless the context otherwise
requires:

(a)   "Board of Directors" means the board of directors of the Corporation.

(b)   "Business  Day"  means  any day  other  than a  Saturday,  Sunday or U.S.
Federal  holiday  or day on which  commercial  banks in the City of New York or
the  States  of  Iowa  or  Wisconsin  are  authorized  or  required  by  law or
executive order to close.

(c)   "Exchange  Offer"  shall have the meaning  set forth in the  Registration
Rights Agreement.

(d)   "Exchange Offer Registration  Statement" shall have the meaning set forth
in the Registration Rights Agreement.

(e)   "Junior Stock" means the Common Stock and any other of the  Corporation's
equity  securities  that by their terms rank junior to the  Series A  Preferred
Stock with  respect to payment of  dividends  and  distribution  of assets upon
the liquidation, dissolution or winding up of the Corporation.

(f)   "Liquidation  Preference"  means $25 per share of the Series A  Preferred
Stock.

(g)   "Parity Stock" means any series of preferred stock established  hereafter
by the Board of  Directors,  the  terms of which  expressly  provide  that such
series will rank on a parity with the  Series A  Preferred  Stock with  respect
to  payment of  dividends  and  distribution  of assets  upon the  liquidation,
dissolution or winding up of the Corporation.

(h)   A "Registration Default" occurs if:

          (i) the Exchange  Offer  Registration  Statement is not filed with the
     SEC on or prior to April 1, 2003;

          (ii) the Exchange Offer  Registration  Statement has not been declared
     effective on or prior to June 1, 2003;

          (iii) the  Exchange  Offer is not  consummated  on or prior to July 1,
     2003; or

<PAGE>

          (iv) if  required,  the Shelf  Registration  Statement is not declared
     effective on or prior to July 1, 2003.

(i)   "Registrable  Securities"  shall  have  the  meaning  set  forth  in  the
Registration Rights Agreement.

(j)   "Registration  Rights Agreement" means the Registration Rights Agreement,
between the  Corporation and Robert W. Baird & Co.  Incorporated,  with respect
to the Series A Preferred Stock.

(k)   "SEC" means the United States  Securities and Exchange  Commission or any
successor  agency  or  government  body  performing  the  functions   currently
performed by the United States Securities and Exchange Commission.

(l)   "Shelf  Registration  Statement"  shall have the meaning set forth in the
Registration Rights Agreement.

(m)   "Transfer  Agent" means the  Shareowner  Services  Department  of Alliant
Energy  Corporation,  as  the  transfer  agent  of  the  Corporation,  and  any
successor transfer agent duly appointed by the Corporation.

Section 8. Headings.  The headings of the Sections are for convenience of
           ---------
reference only and shall not define, limit or affect any of the provisions
hereof.


                  8.375% Series B Cumulative Preferred Stock

Section 1. Designation and Number.
           -----------------------

(a)   There is hereby  created out of the  authorized  but  unissued  Preferred
Stock a series of Preferred  Stock  designated as "8.375%  Series B  Cumulative
Preferred  Stock"  (the  "Series B  Preferred  Stock").  The  number  of shares
constituting the Series B Preferred Stock shall be 6,000,000.

(b)   All  shares  of  the  Series B   Preferred  Stock  redeemed,   purchased,
exchanged,  converted  or  otherwise  acquired  by  the  Corporation  shall  be
retired  and  canceled  and,  upon  the  taking  of  any  action   required  by
applicable  law,  shall be restored to the status of  authorized  but  unissued
shares  of  Preferred  Stock,   without  designation  as  to  series,  and  may
thereafter  be  designated  or  redesignated  and issued or reissued as part of
any series of Preferred Stock.

(c)   Capitalized  terms used herein and not otherwise defined herein or in the
Corporation's  Restated  Articles of Incorporation  shall have the meanings set
forth in Section 7.

Section 2. Ranking.
           --------

(a)   The  Series B  Preferred  Stock  shall rank,  with  respect to payment of
dividends and distribution of assets upon  liquidation,  dissolution or winding
up of the Corporation:

          (i) senior to Junior Stock; and

          (ii) on a parity with Parity Stock.

Section 3. Dividends.
           ----------

(a)   The holders of shares of the Series B  Preferred  Stock shall be entitled
to receive,  when,  as and if declared by the Board of  Directors  out of funds
legally  available  for the payment of dividends,  cash  dividends at an annual
rate of 8.375% of the Liquidation Preference.

(b)   All  dividends  on the  Series B  Preferred  Stock  shall  accrue  and be
cumulative  from the  date of  original  issuance,  subject  to the  following.
Dividends  shall  be  payable  quarterly  in  arrears  on  March  15,  June 15,
September 15  and  December 15  of each year,  beginning on the First  Dividend

<PAGE>

Payment  Date.  If any of those  dates is not a Business  Day,  then  dividends
shall be  payable  on the next  succeeding  Business  Day.  Dividends  shall be
payable  on those  dates to  holders  of  record  as they  appear  in the stock
records of the  Corporation at the close of business on the  applicable  record
date,  which shall be the last  Business Day of the month prior to the month in
which the  applicable  dividend  payment  date falls.  Holders of shares of the
Series A  Preferred Stock exchanged for shares of the Series B  Preferred Stock
will not be entitled to receive any payments  with respect to unpaid  dividends
on shares of the Series A  Preferred  Stock so exchanged.  Notwithstanding  the
foregoing,  on the First  Dividend  Payment  Date,  each share of the  Series B
Preferred  Stock that was issued in exchange for a share of Series A  Preferred
Stock shall  entitle the holder  thereof to receive,  when,  as and if declared
by the Board of Directors  out of funds  legally  available  for the payment of
dividends,  cash  dividends in an amount equal to the  cumulative  dividends to
which the  holder of the shares of the  Series A  Preferred  Stock in  exchange
for which  such share of the  Series B  Preferred  Stock was issued  would have
been entitled had such share of Series A  Preferred  Stock been  outstanding on
the  applicable  record date for such First  Dividend  Payment Date. The amount
of  dividends  payable for the initial  dividend  period or any period  shorter
than a full  dividend  period  shall be computed on the basis of a 360-day year
consisting  of twelve  30-day  months and the actual  number of days elapsed in
the period.

(c)   The Board of Directors  shall not authorize,  and the  Corporation  shall
not pay, any dividends on the Series B  Preferred  Stock or set aside funds for
the payment of dividends if the terms of any of the  Corporation's  agreements,
including  agreements  relating to indebtedness,  prohibit that  authorization,
payment or setting  aside of funds or provide that the  authorization,  payment
or setting  aside of funds is a breach of or a default  under  that  agreement,
or if the  authorization,  payment or setting  aside of funds is  restricted or
prohibited by law.

(d)   Notwithstanding   the  provisions  of  Section 3(f),   dividends  on  the
Series B  Preferred  Stock  shall  accrue  whether or not the  Corporation  has
earnings,  whether or not there are funds legally  available for the payment of
dividends  and whether or not dividends are  authorized.  No interest  shall be
paid in respect of any accrued but unpaid  dividends on the Series B  Preferred
Stock.

(e)   Holders of shares of the Series B  Preferred  Stock shall not be entitled
to any  dividends  in  excess  of full  cumulative  dividends  on the  Series B
Preferred Stock as described  above.  Any dividend payment made on the Series B
Preferred  Stock  shall  first be credited  against  the  earliest  accrued and
unpaid dividend due.

(f)   The Corporation  shall not pay any dividends with respect to Junior Stock
if dividends payable on the Series B Preferred Stock are in arrears.

Section 4. Liquidation Preference.
           -----------------------

(a)   Upon any voluntary or involuntary liquidation,  dissolution or winding up
of the  Corporation,  each  holder of shares of the  Series B  Preferred  Stock
shall be entitled to payment,  out of the  Corporation's  assets  available for
distribution  to  its  shareowners,  of an  amount  equal  to  the  Liquidation
Preference  plus an amount  equal to all accrued and unpaid  dividends on those
shares to, but excluding,  the date of  liquidation,  dissolution or winding up
before any  distribution is made on any Junior Stock.  After payment in full of
the  Liquidation  Preference  and the amount  equal to all  accrued  and unpaid
dividends  to which  holders  of shares  of the  Series B  Preferred  Stock are
entitled,  the holders of the  Series B  Preferred  Stock shall not be entitled
to any further  participation in any distribution of the Corporation's  assets.
If upon any voluntary or  involuntary  liquidation,  dissolution  or winding up
of  the  Corporation,  the  amounts  payable  with  respect  to  shares  of the
Series B  Preferred  Stock and any Parity Stock are not paid in full,  then the
holders  of shares of the  Series B  Preferred  Stock  and the  holders  of the
Parity  Stock  shall  share  equally  and  ratably in any  distribution  of the
Corporation's  assets in proportion to the full distributable  amounts to which
each such holder is entitled.

(b)   Neither the voluntary sale,  conveyance,  exchange or transfer, for cash,
shares of stock,  securities or other  consideration,  of all or  substantially
all of the Corporation's  property or assets nor the  consolidation,  merger or
amalgamation  of  the  Corporation  with  or  into  any  other  entity  or  the
consolidation,  merger or  amalgamation  of any other  entity  with or into the
Corporation  will be  deemed  to be a  voluntary  or  involuntary  liquidation,
dissolution or winding up of the Corporation.

Section 5. Redemption.
           -----------

(a)   The  Corporation  may not redeem the  Series B  Preferred  Stock prior to
March 15,  2013.  On or after  March 15,  2013,  the  Corporation,  at its sole
option,  may  redeem  the  Series B  Preferred  Stock,  out  of  funds  legally

<PAGE>

available  therefor,  in whole or in part  from  time to time at a price of $25
per  share,  plus an amount  equal to  accrued  and  unpaid  dividends  to, but
excluding, the redemption date (the "Redemption Price").

(b)   In the case of any partial  redemption,  the  Corporation  may select the
shares of the Series B  Preferred  Stock to be redeemed on a pro rata basis, by
lot or any other method that the  Corporation,  in its  discretion,  deems fair
and   appropriate.   However,   the   Corporation   may,   without   regard  to
proportionality  or any other factor,  redeem all of the shares of the Series B
Preferred  Stock held by any  holders of fewer than 100 shares of the  Series B
Preferred  Stock (or all the  shares of the  Series B  Preferred  Stock held by
holders who would hold fewer than 100 shares of the  Series B  Preferred  Stock
as a result of such redemption).

(c)   If the Corporation  elects to redeem the Series B  Preferred Stock in the
manner  described  in this  Section 5,  then  notice  of such  redemption  (the
"Redemption  Notice")  shall be given to the holders of record of shares of the
Series B  Preferred  Stock not less than 45 nor more  than 90 days  before  the
date of the redemption (the  "Redemption  Date");  provided,  however,  that no
failure  to give such  Redemption  Notice on or any  deficiency  therein  shall
affect the validity of the  procedure  for the  redemption of any shares of the
Series B  Preferred  Stock to be redeemed except as to the holder or holders to
whom the  Corporation  has failed to give said  Redemption  Notice or except as
to the holder or  holders  whose  Redemption  Notice  was  defective.  All such
Redemption Notices shall state:

          (i) the Redemption Date;

          (ii) the Redemption Price;

          (iii) the total number of shares of the Series B Preferred Stock to be
     redeemed;

          (iv) that the  Redemption  Price will  become  due and  payable on the
     Redemption  Date upon each such  share of  Series B  Preferred  Stock to be
     redeemed and that  dividends  thereon will cease to accrue on and after the
     Redemption Date; and

          (v) the place or places where  certificates for the Series B Preferred
     Stock are to be surrendered for payment of the Redemption Price.

(d)   Prior to any  Redemption  Date,  the  Corporation  shall  deposit  with a
designated  bank or trust  company as paying agent (or, if the  Transfer  Agent
or the  Corporation  is  acting  as the  paying  agent,  segregate  and hold in
trust) an amount of  consideration  sufficient to pay the  Redemption  Price of
all shares of  Series B  Preferred  Stock which are to be redeemed on that date
other than any  Series B  Preferred  Stock called for prior to the date of such
deposit.

(e)   Notice  of  redemption   having  been  given  as  described   above,  the
Redemption  Price of the Series B  Preferred Stock to be redeemed shall, on the
Redemption Date,  become due and payable,  and from and after such date (unless
the  Corporation  shall default in the payment of the Redemption  Price),  such
shares of Series B  Preferred Stock shall no longer be  outstanding,  dividends
on such  Series B  Preferred  Stock  shall  cease to accrue  and all  rights of
holders  thereof  as  shareowners  of the  Corporation  (except  the  right  to
receive the Redemption  Price without  interest)  shall cease.  Upon book-entry
transfer  or  surrender  of any  certificate  representing  any  such  share of
Series B  Preferred Stock for redemption in accordance  with said notice,  such
Redemption Price shall thereupon be paid.

(f)   If any  certificate  that  represents  more  than one  share of  Series B
Preferred  Stock,  not all of which are subject to  redemption,  is surrendered
at any office or agency of the  Corporation  designated for that purpose (with,
if the  Corporation or the Transfer Agent so requires,  due  endorsement by, or
a written  instrument of transfer in form  satisfactory  to the Corporation and
the  Transfer  Agent duly  executed  by, the  holder  thereof or such  holder's
attorney duly authorized in writing),  the Corporation  shall execute,  and the
Transfer  Agent  shall  deliver  to the  holder  of  such  shares  of  Series B
Preferred  Stock without service  charge,  a new  certificate or  certificates,
representing  any number of shares of Series B  Preferred  Stock,  as requested
by such  holder,  in an  aggregate  amount  equal to the  number of shares  not
redeemed and represented by the certificate so surrendered.

(g)   Payment  of the  Redemption  Price for the  Series B  Preferred  Stock is
conditioned upon book-entry  transfer or physical  delivery of the certificates
representing   the  Series B   Preferred   Stock,   together   with   necessary

<PAGE>

endorsements  to  the  Transfer  Agent  at  any  time  after  delivery  of  the
Redemption  Notice.  Payment of the Redemption Price for the Series B Preferred
Stock will be made  promptly  following  the later of the  Redemption  Date and
the time of  book-entry  transfer  or  physical  delivery  of the  certificates
representing the Series B Preferred Stock subject to redemption.

(h)   If the Transfer Agent holds money  sufficient to pay the Redemption Price
of the Series B  Preferred  Stock on the Redemption Date in accordance with the
terms of this Section 5,  then, on the Redemption Date, the Series B  Preferred
Stock  will cease to be  outstanding,  whether or not  book-entry  transfer  is
made or certificates  representing  the Series B  Preferred Stock are delivered
to the  Transfer  Agent.  At such  time,  all rights of a holder as a holder of
Series B  Preferred Stock shall terminate,  other than the right to receive the
Redemption Price.

(i)   If the  Redemption  Date falls after a dividend  payment  record date and
before the related  dividend  payment  date,  then the holders of the shares of
Series B  Preferred  Stock at the close of  business on that  dividend  payment
record date will be entitled to receive the  dividend  payable of those  shares
on the  corresponding  dividend  payment date.  However,  the Redemption  Price
payable on such  Redemption  Date will not include  dividends  accruing on that
dividend  payment  record  date  and  payable  on  the  corresponding  dividend
payment date.

Section 6. Voting Rights.
           --------------

(a)   The  shares of  Series B  Preferred  Stock  shall  have no voting  rights
except as set forth in this Section 6 or as otherwise provided by Iowa law.

(b)   In the  event  that  any four  quarterly  cumulative  dividends,  whether
consecutive  or not,  payable on the Series B  Preferred  Stock are in arrears,
the  holders of the  Series B  Preferred  Stock  shall  have the right,  voting
separately  as a class  together  with  holders of any Parity  Stock upon which
like  voting  rights  have  been  conferred  and are  exercisable,  at the next
meeting of  shareowners  called for the  election  of  directors,  to elect two
members of the Board of  Directors.  The right of such  holders of the Series B
Preferred  Stock to elect  members  of the Board of  Directors  shall  continue
until such time as all dividends  accumulated  and in arrears on such shares of
the Series B  Preferred  Stock have been paid in full, at which time such right
will  terminate,   subject  to  revesting  in  the  event  of  each  and  every
subsequent  failure to pay dividends as described  above.  Upon any termination
of the  right  of the  holders  of the  Series B  Preferred  Stock to vote as a
class  for  directors,  the term of  office  of all  directors  then in  office
elected by such holders voting as a class will terminate immediately.

(c)   Without  the  affirmative  vote or  consent  of the  holders  of at least
two-thirds of the outstanding  shares of the Series B  Preferred Stock,  voting
as a single  class,  or voting as a single class  together  with holders of any
other  series of Preferred  Stock (i) upon which like voting or consent  rights
have been  conferred and (ii) which are similarly  affected by the matter to be
voted upon, the Corporation shall not:

          (i) increase the amount of authorized shares of the Preferred Stock or
     create or issue  any  class of stock in  addition  to the  Preferred  Stock
     ranking  senior to or on a parity with the Preferred  Stock,  or any series
     thereof, as to the payment of dividends or the distribution of assets;

          (ii) adopt any amendment to the Restated  Articles of Incorporation of
     the Corporation that adversely alters the preferences, powers and rights of
     the Series B Preferred Stock (provided, that Articles of Amendment to issue
     a series of Preferred  Stock shall not be considered to adversely alter the
     preferences,  powers  and  rights of the Series B  Preferred  Stock  solely
     because  such series is on parity  with the Series B  Preferred  Stock with
     respect to payment of dividends and distribution of assets);

          (iii)  issue  any  shares  of  Preferred  Stock of any  series  if the
     cumulative  dividends  payable  on  the  Series B  Preferred  Stock  are in
     arrears; or

          (iv) create or issue any shares of Preferred  Stock of any series that
     rank senior to the Series B  Preferred  Stock as to payment of dividends or
     the distribution of assets.

(d)   On any  matter set forth in  Section 6(b)  or  Section 6(c)  in which the
holders of the Series B  Preferred Stock are entitled to vote as a class,  such
holders  will be entitled to one vote per share.  On any other matter for which
holders  of the  Series B  Preferred  Stock  are  provided  the  right  to vote
together  with holders of the Common  Stock under Iowa law, if any,  holders of

<PAGE>

the  Series B  Preferred  Stock  will be  entitled  to the  number of votes per
share determined by dividing the Liquidation Preference of such share by 100.

Section 7. Certain Definitions.  As used in this Amendment, the following
           --------------------
terms shall have the following meanings, unless the context otherwise
requires:

(a)   "Board of Directors" means the board of directors of the Corporation.

(b)   "Business  Day"  means  any day  other  than a  Saturday,  Sunday or U.S.
Federal  holiday  or day on which  commercial  banks in the City of New York or
the  States  of  Iowa  or  Wisconsin  are  authorized  or  required  by  law or
executive order to close.

(c)   "First  Dividend  Payment Date" means the first dividend  payment date to
occur  following the date on which shares of the Series B  Preferred  Stock are
first issued in exchange for shares of the Series A Preferred Stock.

(d)   "Junior Stock" means the Common Stock and any other of the  Corporation's
equity  securities  that by their terms rank junior to the  Series B  Preferred
Stock with  respect to payment of  dividends  and  distribution  of assets upon
the liquidation, dissolution or winding up of the Corporation.

(e)   "Liquidation  Preference"  means $25 per share of the Series B  Preferred
Stock.

(f)   "Parity Stock" means any series of preferred stock established  hereafter
by the Board of  Directors,  the  terms of which  expressly  provide  that such
series will rank on a parity with the  Series B  Preferred  Stock with  respect
to  payment of  dividends  and  distribution  of assets  upon the  liquidation,
dissolution or winding up of the Corporation.

(g)   "Transfer  Agent" means the  Shareowner  Services  Department  of Alliant
Energy  Corporation,  as  the  transfer  agent  of  the  Corporation,  and  any
successor transfer agent duly appointed by the Corporation.

Section 8. Headings.  The headings of the Sections are for convenience of
           ---------
reference only and shall not define, limit or affect any of the provisions
hereof.