Appropriate license for packages

Hi, although this is a little OT, maybe somebody can help me out. Does somebody know of any talks held or articles written about choosing the right license? This would be of particular interest to me with reference to packages (like the ones shipped by PEAR). When reading the PHP license again I recently thought there might be paragraphs in it which completely don't go together with PEAR packages (not only but e.g. even the closing sentence "This product includes the Zend Engine" - which is not included when we distribute packages). Regards, Stefan