Error for mismatched properties

We currently have:


Most properties may be applied multiple times (for instance two binds to 
the same node, each specifying a constraint); multiple properties of the 
same type are combined so that all have to apply, or that at least one has 
to apply, as in the following overview table. An xforms-binding-error 
<https://www.w3.org/community/xformsusers/wiki/XForms_2.0/submit#The_xforms-binding-error_Event>  
is dispatched to any element that has a binding that applies disallowed 
properties twice to the same node.




<bind ref="x" whitespace="remove"/>


...


<input ref="x" whitespace="trim"/>


Is disallowed. is binding-error a good error event, or do we want to create 
a property-error for such errors?


Steven