UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                  SCHEDULE 13G


                    Under the Securities Exchange Act of 1934

                                (Amendment No. 2)



                          Ottawa Savings Bancorp, Inc.
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                                (Name of Issuer)

                     Common Stock, par value $0.01 per share
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                         (Title of Class of Securities)

                                    68955R102
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                                 (CUSIP Number)

                                December 31, 2006
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             (Date of Event Which Requires Filing of this Statement)


Check the  appropriate box to designate the rule pursuant to which this Schedule
13G is filed:

               [ ] Rule 13d-1(b)
               [X] Rule 13d-1(c)
               [ ] Rule 13d-1(d)

*The  remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for any  subsequent  amendment  containing  information  which  would  alter the
disclosures provided in a prior cover page.


The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).





CUSIP NO.    68955R102
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1.     Names of Reporting Persons.  Tyndall Capital Partners, L.P.
       I.R.S. Identification Nos. Of Above Persons (entities only):  13-3594570
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2.      Check the Appropriate Box if a Member of a Group (See Instructions)
           (a)                      (b)
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3.      SEC Use Only
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4.      Citizenship or Place of Organization:   Delaware
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  Number of Shares Beneficially Owned    5.  Sole Voting Power         129,329*
    by Each Reporting Person With:           -----------------------------------
                                         6.  Shared Voting Power             0
                                             -----------------------------------
                                         7.  Sole Dispositive Power    129,329*
                                             -----------------------------------
                                         8.  Shared Dispositive Power        0
                                             -----------------------------------
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9.      Aggregate Amount Beneficially Owned by Each Reporting Person:   129,329*
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10.     Check if  the Aggregate Amount  in Row (9)  Excludes Certain Shares (See
        Instructions):    N/A
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11.     Percent of Class Represented by Amount in Row (9):   5.8%*
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12.     Type of Reporting Person (See Instructions):   PN
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* As of  December  31,  2006 (the  "Reporting  Date"),  92,209  shares of Ottawa
Savings  Bancorp,  Inc.  common  stock,  par value $0.01 per share (the  "Common
Stock"),  are owned by Tyndall  Partners,  L.P., a Delaware limited  partnership
("Tyndall")  and  37,120  shares  of the  Common  Stock  are  owned  by  Tyndall
Institutional   Partners,   L.P.,  a  Delaware  limited  partnership   ("Tyndall
Institutional"  and,  together  with  Tyndall,  the  "Funds").  Tyndall  Capital
Partners,  L.P.,  a Delaware  limited  partnership  ("Capital"),  is the general
partner of the Funds, and possesses the sole power to vote and the sole power to
direct the disposition of all Common Stock held by the Funds.  Accordingly,  for
the  purposes  of Rule  13d-3  under the  Securities  Exchange  Act of 1934,  as
amended,  Capital is deemed to beneficially  own 129,329 shares of Common Stock,
or 5.8% of those deemed issued and outstanding, as of the Reporting Date.





Item 1.

(a)  Name Of Issuer:   Ottawa Savings Bancorp, Inc.
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(b)  Address  of  Issuer's  Principal  Executive Offices:    925 LaSalle Street,
     Ottawa, Illinois  61350
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Item 2.

(a)  Name of Person Filing:  Tyndall Capital Partners, L.P.
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(b)  Address of Principal Business  Office  or,  if  none, Residence:
     599 Lexington Avenue, Suite 4100, New York, New York  10022
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(c)  Citizenship:  Delaware
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(d)  Title of Class of Securities:  Common Stock, par value $0.01 per share
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(e)  CUSIP Number:  68955R102
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Item  3.  If  this  statement  is  filed  pursuant to  Sections 240.13d-1(b)  or
          240.13d-2(b) or (c), check whether the person filing is a:

          Not Applicable.


Item 4.  Ownership.

         (a)    Amount beneficially owned (as of December 31, 2006):    129,329*

         (b)    Percent of Class (as of December 31, 2006):              5.8%*

         (c)    Number of shares as to which the person has:

            (i)  Sole power to vote or to direct the vote:              129,329*

           (ii)  Shared power to vote or to direct the vote:                  0

          (iii)  Sole power to dispose or to direct the disposition of: 129,329*

           (iv)  Shared power to dispose or to direct the disposition of:     0


* As of  December  31,  2006 (the  "Reporting  Date"),  92,209  shares of Ottawa
Savings  Bancorp,  Inc.  common  stock,  par value $0.01 per share (the  "Common
Stock"),  are owned by Tyndall  Partners,  L.P., a Delaware limited  partnership





("Tyndall")  and  37,120  shares  of the  Common  Stock  are  owned  by  Tyndall
Institutional   Partners,   L.P.,  a  Delaware  limited  partnership   ("Tyndall
Institutional"  and,  together  with  Tyndall,  the  "Funds").  Tyndall  Capital
Partners,  L.P.,  a Delaware  limited  partnership  ("Capital"),  is the general
partner of the Funds, and possesses the sole power to vote and the sole power to
direct the disposition of all Common Stock held by the Funds.  Accordingly,  for
the  purposes  of Rule  13d-3  under the  Securities  Exchange  Act of 1934,  as
amended,  Capital is deemed to beneficially  own 129,329 shares of Common Stock,
or 5.8% of those deemed issued and outstanding, as of the Reporting Date.



Item 5.  Ownership of Five Percent or Less of a Class.

         Not Applicable


Item 6.  Ownership of More Than Five Percent on Behalf of Another Person.

         Not Applicable


Item 7.  Identification  and  Classification  of  the Subsidiary  Which Acquired
         the Security Being Reported on By the Parent Holding Company.

         Not Applicable


Item 8.  Identification and Classification of Members of the Group.

         Not Applicable


Item 9.  Notice of Dissolution of Group.

         Not Applicable


Item 10. Certification.

         By signing  below,  I certify  that, to  the best  of my knowledge  and
belief, the securities  referred to above were not acquired and are not held for
the purpose of or with the effect of changing or influencing  the control of the
issuer of such  securities  and were not acquired and are not held in connection
with or as a participant in any transaction having that purpose or effect.





                                    SIGNATURE

         After reasonable  inquiry and to the best of my knowledge and belief, I
certify that  the information set forth in this statement is  true, complete and
correct.


                                               February 14, 2007


                                               TYNDALL CAPITAL PARTNERS, L.P.

                                               By: JEFFREY MANAGEMENT, L.L.C.,
                                                   its general partner


                                               By: /s/ Jeffrey S. Halis
                                                   -----------------------------
                                                       Jeffrey S. Halis, Manager


      Attention: Intentional misstatements or omissions of fact constitute
                Federal criminal violations (See 18 U.S.C. 1001)