Add path file page/template

<block type="core/template" name="footerblock" template="page/template/footerblock.phtml" >
<block type="core/template" name="copyright" template="page/template/copyright.phtml" />

or

u can direct access on file:

getLayout()->createBlock('core/template')->setTemplate('page/html/footerblock.phtml')->toHtml();

Add path file page/template

<block type="core/template" name="footerblock" template="page/template/footerblock.phtml" >
<block type="core/template" name="copyright" template="page/template/copyright.phtml" />

or

U can direct access this code on footer file:

getLayout()->createBlock('core/template')->setTemplate('page/html/footerblock.phtml')->toHtml();