EXHIBIT A (ADDITIONAL SIGNATURE PAGE TO JOINT FILING AGREEMENT) AGREEMENT REGARDING THE JOINT FILING OF SCHEDULE 13G THE UNDERSIGNED HEREBY AGREE AS FOLLOWS: (1) EACH OF THEM IS INDIVIDUALLY ELIGIBLE TO USE THE SCHEDULE 13G TO WHICH THIS EXHIBIT IS...Joint Filing Agreement • March 12th, 2007 • Vector Later Stage Equity Fund L P • Electromedical & electrotherapeutic apparatus
