dynamic legend from raster

[Mark Brooks]

I have a raster layer that contains precipitation data.  The layer is 
dynamically created and may contain values from 0 to 2.5  or  0 to 35 or 
0 to x.  I want my legend of colors, representing thresholds of 
precipitation values, to be dynamic based on the max and min of the 
layer.  So if the precipitation only goes from 0 to 2.5, then my legend 
has its colors evenly divided up within the 0 to 2.5 threshold.  If the 
layer's precipitation goes from 0 to 35, then my legend will have its 
colors evenly divided up within the 0 to 35 threshold.  To potentially 
complicate things, I also want these colors to be dynamically labeled 
based on what thresholds they represent.  I suspect I should use 
something like PROCESSING SCALE_BUCKETS?  I don't know enough about 
scale buckets to know if it's even appropriate for this.

Any insight?

Thanks,
Mark