>  It works on my eclipse but in may application change only the attribute 
> but don't zap anithing, i don't know the version of trasformer of my 
> application at now.
> there's another way to zap some nodes?

This seems very unlikely. If an XSLT system is so broken that a template
matching 
  <xsl:template match="cup:TipoEsenzione"/>

isn't activated by an element of that name, then it would be impossible
to guess any code that would have any predictable effect on that system.

David