IMSI, a developer of design, graphics and business productivity software, today announced it has entered into a definitive agreement to acquire Aladdin Systems for cash, stock and a convertible note with a combined value of US$8 million dollars and an earn-out that could result in an additional $2 million in payments during the next three years. Aladdin develops and publishes several popular Mac products, including StuffIt, Spring Cleaning and the Ten for X utility line.