Exhibit 23.9 CONSENT OF INDEPENDENT AUDITORS We consent to the incorporation by reference in the Registration Statement (Form S-8) of Genesys S.A. pertaining to the Vialog Corporation 1999 Stock Option Plan of the reference to our firm under the caption "Experts" and of our report dated 26 September 2000, with respect to the financial statements of VideoWeb Limited, included in the Registration Statement (Form F-4 No. 333-55392) of Genesys S.A. filed with the Securities and Exchange Commission. /s/ Ernst & Young ERNST & YOUNG London, England 1 May 2001