X0202 4 2005-12-28 0 0000754813 ION NETWORKS INC IONN 0001044321 MARXE AUSTIN W & GREENHOUSE DAVID M 527 MADISON AVENUE SUITE 2600 NEW YORK NY 10022 0 0 1 0 Common Stock 2005-12-28 4 P 0 20000 0.1494 A 4856571 I By Limited Partnerships This is a joint filing by Austin W. Marxe (Marxe) and David M. Greenhouse (Greenhouse). They share voting and investment control over all securities owned by Special Situations Cayman Fund, L.P. (Cayman), Special Situations Private Equity Fund, LP (PE), Special Situations Technology Fund, L.P. (Tech) and Special Situations Technology II, L.P. (Tech II), respectively. 1,272,647 shares of Common Stock and 604,324 Wts are held by Cayman, 1,365,753 shares of Common Stock and 666,476 Wts are held by PE, 98,321 shares of Common Stock and 50,780 Wts are held by Tech and 527,626 shares of Common Stock and 270,644 are held by Tech II. The interest of Marxe and Greenhouse in the shares of Common Stock owned by Cayman, PE, Tech, and Tech II is limited to the extent of his pecuniary interest. Austin W. Marxe 2005-12-29 David M. Greenhouse 2005-12-29