memory leaks on 1.7 xerces

On tomcat 7 + jdk 1.7
org.apache.xerces.jaxp.datatype.DatatypeFactoryImp l is responsable of blocking the gc of org.apache.catalina.loader.WebappClassLoader.

As JDK 7 comes with a JAXB implementation, do you think it could be better to import spring-security-saml2-core like this in a webapp ?

compile ("org.springframework.security.extensions:sprin g-security-saml2-core:$springSecuritySamlVersion")
{
exclude group: "org.slf4j", module: "jcl-over-slf4j"
exclude group: "org.slf4j", module: "log4j-over-slf4j"
exclude group: "org.apache.xerces", module: "xml-apis"
exclude group: "org.apache.xerces", module: "serializer"

---> exclude group: 'xerces', module: 'xercesImpl'
---> exclude group: 'xml-apis', module: 'xml-apis'
}

seems to working fine without it.