My PZ40X C2 uses all the automatic features on my SX10 IS including
focus flash for the zoom setting.  Make sure you have the Canon model.  
They also have Nikon and Sony compatible models.

€ Flash Control Mode: Canon E-TTL II
€ Guide number of 130 (ISO 100/feet) @ 80mm
€ Auto focus assist for low light shooting up to 16 feet
€ Bounce flash head with five positions
€ LCD display and easy-to-use controls
€ Seven manual power ratios selections
€ Automatic and manual zoom head settings
€ Powered by 2 AA batteries
€ Autofocus assist light
€ Weight: 7.1 ounces (without batteries)