Exhibit 5.1 KRAMER LEVIN NAFTALIS & FRANKEL LLP 919 THIRD AVENUE NEW YORK, NY 10022 - 3852 PARIS TEL 212-715-9100 47, AVENUE HOCHE 75008 FAX 212-715-8000 TEL (33-1) 44 09 46 00 FAX (33-1) 44 09 46 01 November 19, 2003 Internet Commerce Corporation 805 Third Avenue New York, New York 10022 Re: Internet Commerce Corporation Amendment No. 1 to Form S-3 File No. 333-107590 ----------------------------- Ladies and Gentlemen: We have acted as counsel to Internet Commerce Corporation, a Delaware corporation (the "Registrant"), in connection with the preparation and filing of Amendment No. 1 to the Registration Statement on Form S-3, file no. 333-107590 (the "Registration Statement") with the Securities and Exchange Commission (the "SEC") with respect to the registration under the Securities Act of 1933, as amended (the "Act"), of an aggregate of 3,471,091 shares (the "Shares") of class A common stock, par value $0.01 per share (the "Common Stock"), of the Registrant, which includes 1,585,525 shares of Common Stock issuable upon the exercise of warrants and 192,307 shares of Common Stock issuable upon conversion of series D convertible preferred stock, par value $0.01 per share (the "Series D Preferred"). In connection with the registration of the Shares, we have reviewed copies of the following documents: 1. the Registration Statement; 2. the Amended and Restated Certificate of Incorporation of the Registrant, as amended; 3. the By-laws of the Registrant; 4. the Certificate of Designations of the Series D Preferred (the "Certificate of Designations"); 5. the Subscription Agreement dated April 30, 2003 between the Registrant and purchasers of the Common Stock identified therein; 6. the Subscription Agreement dated April 30, 2003 between the Registrant and purchaser of the Series D Preferred identified therein; 7. the form of Warrant Agreement dated April 30, 2003; 8. the form of Warrant Agreement dated May 1, 2003; 9. the Accounts Receivable Financing Agreement dated as of May 30, 2003 between the Registrant and Silicon Valley Bank, a California-chartered bank (the "Bank"); 10. the Registration Rights Agreement dated May 30, 2003 by and among the Registrant and the Bank; Internet Commerce Corporation November 19, 2003 Page 2 11. the Warrant to Purchase Stock dated May 30, 2003 and issued to the Bank; 12. resolutions of the Board of Directors of the Registrant; and 13. such other documents and records as we have deemed necessary to enable us to express an opinion on the matters covered hereby. In rendering this opinion, we have: (a) assumed (i) the genuineness of all signatures on all documents reviewed by us, (ii) the authenticity of all documents submitted to us as originals and (iii) the conformity to original documents of all documents submitted to us as photostatic or conformed copies and the authenticity of the originals of such copies; and (b) relied on (i) representations, statements and certificates of public officials and others and (ii) as to matters of fact, statements, representations and certificates of officers and representatives of the Registrant. Based upon the foregoing, we are of the opinion that the Shares covered by the Registration Statement have been or, in the case of Shares issuable upon (i) exercise of warrants, when issued in accordance with the terms of such warrants, and (ii) conversion of the Series D Preferred, when issued in accordance with the terms of the Certificate of Designations, will be validly issued, fully paid and non-assessable. We hereby consent to the use of this opinion as an exhibit to the Registration Statement. In giving the foregoing consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Securities and Exchange Commission thereunder. We do not express any opinion with respect to any law other than the General Corporation Law of the State of Delaware and the federal laws of the United States of America. Our opinion is rendered only with respect to the laws which are currently in effect in such jurisdictions. Very truly yours, /s/ Kramer Levin Naftalis & Frankel LLP