How can one include a component inside an article in joomla.

I have tried using the Plugin Include Component in Joomla. I have a Phoca guestbook set up which works fine on its own.

But when I try to include it inside an article using

{component url='index.php?option=com_phocaguestbook'}  

It just does not display any component.

This same procedure will work fine for other components.

Any idea about what i am missing here?