namespace defaulting

[Terrence Brannon]

In sidebar.xml you see this:

<sb:sidebar xmlns:sb="http://axkit.org/NS/sidebar-1.0";>

         <sb:section>
                 <sb:title>About AxKit</sb:title>
                 <sb:item>
                         <sb:title>Index</sb:title>
                         <sb:url>/index.xml</sb:url>

is there someway to do something like a Perl "package" directive 
so that all follow declaractions belong to that namespace?