[mapserver-users] how to map_layer_class_name in 6.4.0?

[zach cruise]

in the past, I could do a runtime substitution of a class name by
passing it like so:

..&map_layer1_class1_name=new_name

where in the map file, I had:

MAP
 LAYER
  NAME "layer1"
  CLASS
   NAME "class1"

and in the legend file, I had:

[leg_class_name]

so what changed?