Exhibit 99.2 Certification Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (Subsections (a) and (b) of Section 1350, Chapter 63 of Title 18, United States Code) Pursuant to section 906 of the Sarbanes-Oxley Act of 2002 (subsections (a) and (b) of section 1350, chapter 63 of title 18, United States Code), each of the undersigned officers of deltathree, Inc., a Delaware corporation (the " Company"), does hereby certify, to such officer's knowledge, that: The Annual Report on Form 10-K/A for the year ended December 31, 2002 (the "Form 10-K/A") of the Company fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, and the information contained in the Form 10-K/A fairly presents, in all material respects, the financial condition and results of operations of the Company. Dated: April 29, 2003 /s/ Shimmy Zimels ------------------ Shimmy Zimels Chief Executive Officer Dated: April 29, 2003 /s/ Paul C. White --------------------------- Paul C. White Chief Financial Officer This certification accompanies each Report pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 and shall not, except to the extent required by the Sarbanes-Oxley Act of 2002, be deemed filed by the Company for purposes of Section 18 of the Securities Exchange Act of 1934, as amended.