Recently I found a realy good class to convert bbCode to HTML.

[www.phpclasses.org]

Realy easy to use

	include_once("includes/classes/bbcode.inc.php");
	
	function bbCode2HTML($entry) {
		$entry = nl2br($entry);
		$bbcode = new bbcode();
		$bbcode->add_tag(array('Name'=>'b',
                                            'HtmlBegin'=>'<span style="font-weight: bold;">',
                                            'HtmlEnd'=>'</span>'));
		$bbcode->add_tag(array('Name'=>'i',
                                            'HtmlBegin'=>'<span style="font-style: italic;">',
                                            'HtmlEnd'=>'</span>'));
		$bbcode->add_tag(array('Name'=>'u',
                                            'HtmlBegin'=>'<span style="text-decoration: underline;">',
                                            'HtmlEnd'=>'</span>'));
		$bbcode->add_tag(array('Name'=>'red',
                                            'HtmlBegin'=>'<span style="color: red;">',
                                            'HtmlEnd'=>'</span>'));
		return( $bbcode->parse_bbcode($entry) );
	}

What I liked is that you can define the tags you want to convert and even add your own.
Very nice work.