Help with a UBB Code style parser...

Hi all... I already have a bbcode style parser for my content ie: $output = str_replace("[b]",'<b>',$output); $output = str_replace("[/b]",'</b>',$output); $output = str_replace("[i]",'<i>',$output); $output = str_replace("[/i]",'</i>',$output); $output = str_replace("[img]",'<img src=\"',$output); $output = str_replace("[/img]",'\">',$output); etc... But I need to make a link parser ie: [url=http://xxx.xxx/blah]Link Title[/url] to produce a link of <a href="http://xxx.xxx/blah" target="_new">Link Title</a> Thanks guys!!!!! ;o)