Subversion and Subclipse keywords are not enabled by default.  To get $Id$ to be automatically picked up, you must make a change to the Subclipse configuration file.  On Vista / Windows Server 2008, edit the file <drive>:\Users\<user>\Application Data\Subversion\config.  NOTE: with UAC enabled, you will need to open your command prompt with the "Run As Administrator" option to provide the requisite permissions.

  1. uncomment the line that contains 'enable-auto-props' and make sure it is set to 'yes'
  2. add file types and keyword support in the section [auto-props]

For example:

[auth]
[helpers]
[tunnels]
[miscellany]
enable-auto-props = yes
[auto-props]
*.pl = svn:eol-style=native;svn:keywords=Id Author Date Revision
*.php = svn:eol-style=native;svn:keywords=Id Author Date Revision
*.txt = svn:eol-style=native;svn:keywords=Id Author Date Revision
*.ini = svn:eol-style=native;svn:keywords=Id Author Date Revision

On UNIX, this can be done by editing the file ~/.subversion/config and making the same edits.