Currently PEAR supports the following list of licenses:
   
- 
      PHP License
      
- 
      Apache License
      
- 
      LGPL
      
- 
      BSD style
      
- 
      MIT License
      
    Other licenses may be added to this list on a case-by-case
    basis. Please get in touch with the PEAR developers mailing list
    for this.
   
    For PECL extensions that are linked into PHP, the license
    must be compatible with the PHP license.  That means you can not GPL
    a PECL extension or you would be violating the GPL.  Note also that if
    you write an extension that links against a GPL'ed library you will be
    violating the GPL.  If you need to link against a GPL'ed library, get
    permission from the author of the library.
   
    To set the license of you PEAR/PECL package, put it in the head of
    all source code files of your package and also the type of it
    inside the <license> tag of your package description file
    (package.xml).