EXHIBIT 4.12

To Bank Hapoalim B.M.                                    Date: December 5, 2004


Dear Sir/Madam

                                 RE: UNDERTAKING

Whereas we have obtained and/or are about to obtain the credits and other
banking services from you and we have also executed and/or will execute the
undertakings and guarantees in order to guarantee our indebtedness and other
parties' undertakings to you (hereinafter: "the Credit");

Accordingly from the date of this letter, and so long as our indebtedness to you
has not been extinguished, we hereby undertake to maintain our financial
covenants, as detailed in our annual consolidated financial statements prepared
in U.S. dollars and in accordance with U.S. GAAP, as follows:

1.   As of any applicable balance sheet date, the total shareholders' equity
     will not be less than $30,000,000 and the ratio of the total shareholders'
     equity to total assets will not be, less than 40%.

2.   At any time, a sum of no less than US$15,000,000 (Fifteen Million US
     Dollars) will be deposited (in manner of cash or securities) with the
     Company, net of interest-bearing commercial or financial debt.

     The terms set out above will be construed in accordance with U.S. GAAP.

3.   We hereby undertake to provide you will full quarterly reports as filed by
     us with the SEC, for information purposes only, as to our assets, profits,
     sales and in respect of our other financial commitments, as well as an
     audited annual balance sheet within 120 days from the end of each calendar
     year.

4.   We are aware that should we breach the said undertaking, you will be
     entitled to take any measures as you see fit against us, including and not
     limited to, requesting immediately repayment of all our debts and financial
     undertakings on your behalf, this being in addition to any other relief
     and/or measure that you are entitled to, pursuant to the various documents
     that we have signed and/or shall be signed in your favor.

5.   These undertakings are irrevocable and we shall not be entitled to cancel
     and/or amend them without your prior written consent.

6.   The aforementioned does not derogate from, but rather is an addition to,
     the other undertakings, pursuant to various other documents that we have
     signed and/or shall sign, in favor of yourselves.

     Yours sincerely,

     /s/ Aviv Boim
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     ORCKIT COMMUNICATION LTD.




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I, the undersigned ADAM KLEIN Adv., acting as the legal counsel of ORCKIT
COMMUNICATION LTD. No. 52-004287-0 (the "COMPANY"), hereby confirm that the
Company signed upon the above document through its authorized signatory Mr.
Izhak Tamir, President, and/or Mr. Aviv Boim, Chief Financial Officer, according
to a resolution duly adopted on DECEMBER 1, 2004, and to its constituting
documents, and I further confirm that the above signature is binding upon the
Company for any intent or purpose.


/s/ Adam Klein                                                          7/12/04
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STAMP AND SIGNATURE OF LEGAL COUNSEL                                      DATE



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