To see more options, check out svn_pre_commit
#!/usr/bin/php
<?php
//set the file types
$file_types = array('php', 'inc');
new svn_hooks($argv[1], $argv[2], array(
//at least 3 characters in your commit message
'LogMessageLength' => array(3),
//php lint these files
'PHPLint' => array($file_types),
//check these files for debug output
'DebugOutput' => array($file_types)
));