What is the diffrence between a CMS and a Framework?
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I am currently working with Zend Framework and I am extremely happy with it. What I want to know is at what kind of requirements it is better to use CMS's like joomla or drupal.

Considering my current project it is a portal application. It is completely made from scratch in Zend. Then some fellow comes and comment that it rather implemented in drupal you could get plugins for the stuff you built by hard efforts. 

So I need a guideline for how to choose between CMS and A Framework at the kickoff phase?.   