Tengo la siguiente clase: http://www.phpclasses.org/package/3245-PHP-Automatically-suggest-keywords-from-content-text.html

<?php
class autokeyword {
 
	//declare variables
	//the site contents
	var $contents;
	var $encoding;
	//the generated keywords
	var $keywords;
	//minimum word length for inclusion into the single word
	//metakeys
	var $wordLengthMin;
	var $wordOccuredMin;
	//minimum word length for inclusion into the 2 word
	//phrase metakeys
	var $word2WordPhraseLengthMin;
	var $phrase2WordLengthMinOccur;
	//minimum word length for inclusion into the 3 word
	//phrase metakeys
	var $word3WordPhraseLengthMin;
	//minimum phrase length for inclusion into the 2 word
	//phrase metakeys
	var $phrase2WordLengthMin;
	var $phrase3WordLengthMinOccur;
	//minimum phrase length for inclusion into the 3 word
	//phrase metakeys
	var $phrase3WordLengthMin;
 
	function autokeyword($params, $encoding)
	{
 
		//get parameters
		$this->encoding = $encoding;
 
		mb_internal_encoding($encoding);
 
		$this->contents = $this->replace_chars($params['content']);
 
		// single word
		$this->wordLengthMin = $params['min_word_length'];
		$this->wordOccuredMin = $params['min_word_occur'];
 
		// 2 word phrase
		$this->word2WordPhraseLengthMin = $params['min_2words_length'];
		$this->phrase2WordLengthMin = $params['min_2words_phrase_length'];
		$this->phrase2WordLengthMinOccur = $params['min_2words_phrase_occur'];
 
		// 3 word phrase
		$this->word3WordPhraseLengthMin = $params['min_3words_length'];
		$this->phrase3WordLengthMin = $params['min_3words_phrase_length'];
		$this->phrase3WordLengthMinOccur = $params['min_3words_phrase_occur'];
 
		//parse single, two words and three words
 
	}
 
	function get_keywords()
	{
		$keywords = $this->parse_words().$this->parse_2words().$this->parse_3words();
		return substr($keywords, 0, -2);
	}
 
	//turn the site contents into an array
	//then replace common html tags.
	function replace_chars($content)
	{
		//convert all characters to lower case
		$content = mb_strtolower($content);
		//$content = mb_strtolower($content, "UTF-8");
		$content = strip_tags($content);
 
		$punctuations = array(',', ')', '(', '.', "'", '"',
		'<', '>', '!', '?', '&ldquo;', '&rdquo;', '/', '-',
		'_', '[', ']', ':', ';', '+', '=', '#',
		'$', '&quot;', '&copy;', '039;', 'nbsp;', 'nbsp',
		'&aacute;', '&eacute;', '&bull;', 'bull;', 'aacute', 'eacute', 'uacute', 'ntilde', 'Ntilde', 'oacute', 'iacute', '&iacute;', 
		'&oacute;', '&uacute', '&nbsp;', '&iquest;', '&hellip;', 'hellip', '&iexcl;', 'iexcl;', 'iquest;', 'iquest', 'iexcl', 'nbsp;', '&ntilde', 'mdash;', '&mdash;', 'mdash', '&mdash', 'ldquo;', '&ldquo;', 'ldquo', '&ldquo', 'rdquo;', '&rdquo;', 'rdquo', '&rdquo', '&Ntilde', '&039;', '&', '&gt;', '&lt;',
		chr(10), chr(13), chr(9));
 
		$content = str_replace($punctuations, " ", $content);
		// replace multiple gaps
		$content = preg_replace('/ {2,}/si', " ", $content);
 
		return $content;
	}
 
	//single words META KEYWORDS
	function parse_words()
	{
		//list of commonly used words
		// this can be edited to suit your needs
		$common = array("m&aacute;s", "039;m");
		//create an array out of the site contents
		$s = split(" ", $this->contents);
		//initialize array
		$k = array();
		//iterate inside the array
		foreach( $s as $key=>$val ) {
			//delete single or two letter words and
			//Add it to the list if the word is not
			//contained in the common words list.
			if(mb_strlen(trim($val)) >= $this->wordLengthMin  && !in_array(trim($val), $common)  && !is_numeric(trim($val))) {
				$k[] = trim($val);
			}
		}
		//count the words
		$k = array_count_values($k);
		//sort the words from
		//highest count to the
		//lowest.
		$occur_filtered = $this->occure_filter($k, $this->wordOccuredMin);
		arsort($occur_filtered);
 
		$imploded = $this->implode(", ", $occur_filtered);
		//release unused variables
		unset($k);
		unset($s);
 
		return $imploded;
	}
	function parse_2words()
	{
		//create an array out of the site contents
		$x = split(" ", $this->contents);
		//initilize array
 
		//$y = array();
		for ($i=0; $i < count($x)-1; $i++) {
			//delete phrases lesser than 5 characters
			if( (mb_strlen(trim($x[$i])) >= $this->word2WordPhraseLengthMin ) && (mb_strlen(trim($x[$i+1])) >= $this->word2WordPhraseLengthMin) )
			{
				$y[] = trim($x[$i])." ".trim($x[$i+1]);
			}
		}
 
		//count the 2 word phrases
		$y = @array_count_values($y);
 
		$occur_filtered = $this->occure_filter($y, $this->phrase2WordLengthMinOccur);
		//sort the words from highest count to the lowest.
		arsort($occur_filtered);
 
		$imploded = $this->implode(", ", $occur_filtered);
		//release unused variables
		unset($y);
		unset($x);
 
		return $imploded;
	}
 
	function parse_3words()
	{
		//create an array out of the site contents
		$a = split(" ", $this->contents);
		//initilize array
		$b = array();
 
		for ($i=0; $i < count($a)-2; $i++) {
			//delete phrases lesser than 5 characters
			if( (mb_strlen(trim($a[$i])) >= $this->word3WordPhraseLengthMin) && (mb_strlen(trim($a[$i+1])) > $this->word3WordPhraseLengthMin) && (mb_strlen(trim($a[$i+2])) > $this->word3WordPhraseLengthMin) && (mb_strlen(trim($a[$i]).trim($a[$i+1]).trim($a[$i+2])) > $this->phrase3WordLengthMin) )
			{
				$b[] = trim($a[$i])." ".trim($a[$i+1])." ".trim($a[$i+2]);
			}
		}
 
		//count the 3 word phrases
		$b = array_count_values($b);
		//sort the words from
		//highest count to the
		//lowest.
		$occur_filtered = $this->occure_filter($b, $this->phrase3WordLengthMinOccur);
		arsort($occur_filtered);
 
		$imploded = $this->implode(", ", $occur_filtered);
		//release unused variables
		unset($a);
		unset($b);
 
		return $imploded;
	}
 
	function occure_filter($array_count_values, $min_occur)
	{
		$occur_filtered = array();
		foreach ($array_count_values as $word => $occured) {
			if ($occured >= $min_occur) {
				$occur_filtered[$word] = $occured;
			}
		}
 
		return $occur_filtered;
	}
 
	function implode($gule, $array)
	{
		$c = "";
		foreach($array as $key=>$val) {
			@$c .= $key.$gule;
		}
		return $c;
	}
}
?>

Lo que hace la clase es buscar palabras repetidas y mostrarlas
Tengo el siguiente texto
"La convocatoria de reunión es una notificación. Reunión. Reunión. Reunión"
Deberia marcarme Reunión, pero lo que me marca es solamente reuni y se corta.

Alguien sabe a que se debe el problema, o como lo podria arreglar?

La palabra es reunión y no reunión solo

Gracias
Salu2