MAVlink GPS waypoint precision


I am working ArduCopter 3.2.1 on Pixhawk with Mission Planner on Windows 8. I have acquired cm-level accuracy on the copter and am concerned on how the autopilot will respond to this level of accuracy.
From what I understand from other forums and, the raw MAVlink GPS messages are int32, so precision wont be lost there. However, the waypoints us float32, so there will be a loss of precision. I have searched through the forums but could find concrete help on this issue.

Does anybody found a way to increase the precision of the waypoints to maintain cm-level precision?