Signing protocols and assertions

Hi all,

In saml-core specification 5.4.6 example, Response and Assertion were
signed by using <InclusiveNamespaces>. If I sign those by simply using
exc-c14n without
<InclusiveNamespaces> processing, which case will have a trouble ? In
turn, what kind of elements or attributes will make trouble in SAML?

Thanks.

Hideki