FIXME: Look over new file...

there are a few features of package2.xml we will need to take advantage of:

to describe modules as optional dependencies on seagull core

...
 <dependencies>
  <required>
   <package>
    <name>XML_Util</name>
    <channel>pear.php.net</channel>
   </package>
  </required>
  <optional>
   <subpackage>
    <name>seagull_publisher</name>
    <channel>pear.phpkitchen.com</channel>   
   </subpackage>
  </optional>  
  <group hint="use publisher for cms functionality" name="publisher">
    <subpackage>
    <name>seagull_publisher</name>
    <channel>pear.phpkitchen.com</channel>   
   </subpackage>
  </group>  
 </dependencies>
...

to describe a given module's dependency on seagull core package

<?xml version="1.0"?>
<package packagerversion="1.4.0a11" version="2.0" xmlns="http://pear.php.net/dtd/package-2.0" xmlns:tasks="http://pear.php.net/dtd/tasks-1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://pear.php.net/dtd/tasks-1.0
http://pear.php.net/dtd/tasks-1.0.xsd
http://pear.php.net/dtd/package-2.0
http://pear.php.net/dtd/package-2.0.xsd">
 <name>seagull_publisher</name>
 <channel>pear.phpkitchen.com</channel>
 <summary>cms functionality</summary>
 <description>Seagull is a PHP application framework with a number of modules available that deliver CMS functionality
 </description>
 <lead>
  <name>Demian Turner</name>
  <user>demianturner</user>
  <email>demian@phpkitchen.com</email>
  <active>yes</active>
 </lead>
 <date>2005-04-20</date>
 <time>00:59:08</time>
 <version>
  <release>0.4.0</release>
  <api>0.4.0</api>
 </version>
 <stability>
  <release>beta</release>
  <api>beta</api>
 </stability>
 <license uri="http://www.example.com">BSD License</license>
 <notes>See the CHANGELOG for full list of changes
 </notes>
 <contents>
  <dir name="/">
   <dir name="classes">
    <file baseinstalldir="publisher" name="ArticleMgr.php" role="php" />
    <file baseinstalldir="publisher" name="ArticleViewMgr.php" role="php" />
    <file baseinstalldir="publisher" name="ContentTypeMgr.php" role="php" />
    <file baseinstalldir="publisher" name="DocumentMgr.php" role="php" />
    <file baseinstalldir="publisher" name="FileMgr.php" role="php" />
    <file baseinstalldir="publisher" name="Output.php" role="php" />
    <file baseinstalldir="publisher" name="PublisherBase.php" role="php" />
   </dir> <!~~ /classes ~~>
   <dir name="data">
    <file baseinstalldir="publisher" name="constraints.my.sql" role="php" />
    <file baseinstalldir="publisher" name="constraints.oci.sql" role="php" />
    <file baseinstalldir="publisher" name="constraints.pg.sql" role="php" />
    <file baseinstalldir="publisher" name="data.default.my.sql" role="php" />
    <file baseinstalldir="publisher" name="data.default.oci.sql" role="php" />
    <file baseinstalldir="publisher" name="data.default.pg.sql" role="php" />
    <file baseinstalldir="publisher" name="schema.my.sql" role="php" />
    <file baseinstalldir="publisher" name="schema.oci.sql" role="php" />
    <file baseinstalldir="publisher" name="schema.pg.sql" role="php" />
   </dir> <!~~ /data ~~>
   <dir name="lang">
    <file baseinstalldir="publisher" name="brazilian_portuguese-iso-8859-1.php" role="php" />
    <file baseinstalldir="publisher" name="chinese-big5.php" role="php" />
    <file baseinstalldir="publisher" name="chinese-gb2312.php" role="php" />
    <file baseinstalldir="publisher" name="chinese_simplified-utf-8.php" role="php" />
    <file baseinstalldir="publisher" name="chinese_traditional-utf-8.php" role="php" />
    <file baseinstalldir="publisher" name="czech-iso-8859-2.php" role="php" />
    <file baseinstalldir="publisher" name="english-iso-8859-15.php" role="php" />
    <file baseinstalldir="publisher" name="french-iso-8859-1.php" role="php" />
    <file baseinstalldir="publisher" name="french-utf-8.php" role="php" />
    <file baseinstalldir="publisher" name="german-iso-8859-1.php" role="php" />
    <file baseinstalldir="publisher" name="italian-iso-8859-1.php" role="php" />
    <file baseinstalldir="publisher" name="portuguese-iso-8859-1.php" role="php" />
    <file baseinstalldir="publisher" name="russian-windows-1251.php" role="php" />
    <file baseinstalldir="publisher" name="spanish-iso-8859-1.php" role="php" />
   </dir> <!~~ /lang ~~>
   <file baseinstalldir="publisher" name="conf.ini" role="php" />
  </dir> <!~~ / ~~>
 </contents>
 <dependencies>
  <required>
   <php>
    <min>4.0.0</min>
   </php>
   <pearinstaller>
    <min>1.4.0a1</min>
   </pearinstaller>
   <package>
    <name>HTTP_Download</name>
    <channel>pear.php.net</channel>
   </package>
   <package>
    <name>Text_Statistics</name>
    <channel>pear.php.net</channel>
   </package>
   <package>
    <name>seagull</name>
    <channel>pear.phpkitchen.com</channel>
   </package>   
  </required>  
 </dependencies>
 <phprelease />
 <changelog>
  <release>
   <version>
    <release>0.4.0</release>
    <api>0.4.0</api>
   </version>
   <stability>
    <release>beta</release>
    <api>beta</api>
   </stability>
   <date>2005-04-20</date>
   <license uri="http://www.example.com">BSD License</license>
   <notes>See the CHANGELOG for full list of changes
   </notes>
  </release>
 </changelog>
</package>