[resolver] configuring resolver for transformer when using JAXP?

Does anyone have any valuable examples of configuring the resolver to 
work with the underlying transformer via JAXP?

Sepcifically,

Saxon and Xalan both provide "command line" arguments for engaging the 
resolver for resolving uri in the styelsheets. I assume on can easily 
use get/setUriResolver() in both the transformer and the factory for 
this case. But what about dtd resolution in the underlying SAX parser 
that the transformer uses to parse the Sources for the xslt and the xml 
content, can this also be configured?

thanks,
Mark