ajax loading but intermittently in a jsp

Question

All,

I have included some ajax pages in my jsp as in the following way:-

ajaxpage('', 'contentarea')

where content area is a div id

the JS loads the ajax in the following format

document.getElementById('contentarea').innerHTML=page_request.responseText

But the problem is the part thats loaded with ajax is intermittent...

any help

Adhir