type 4 keybord problems

[Wallace Colyer]

We have some sun3/60 that are really upgraded sun3/60's running SunOS 3.5.
The following keys:

	right shift key
	left shift key
	left diamond (X11 meta key)

stop working until the machine has been power cycled. Sometimes a power
cycle doesn't even work.  I have been told that upgrading to 4.0.3 will
solve this, but I am not sure if this is a feasable alternative for us
right now.  

Does anyone know a solution to this?