regex question

I'm trying to parse an existing html file using php. I need to use regex to find the first (and only the first) occurance of <i> and the last (and only the last) occurance of </i> in a string. They will be replaced with ||. example of a string: blah blah <i>some stuff</i> that i <i>need to get</i> blah blah blah. needs to become: blah blah ||some stuff that i need to get|| blah blah blah. so the following is what i need..... //replace outer tags with || $string = ereg_replace ("Some regex that only finds the first <i>","||",$string); $string = ereg_replace ("Some regex that only finds the last </i>","||",$string); //take out remaining (inner) tags. $string = ereg_replace ("<i>","",$string); $string = ereg_replace ("</i>","",$string); thanks Julian