strange stripos behavior

I'm using PHP 5.1 on IIS. I have an app that uses MimeDecode to load mime files and I've built an object to parse them into their various parts; i.e., $msg->Body(), $msg->Sender(), etc. I'm using stripos() to look for a string (that I know is in my test files). It works if I search in $msg->Body(), but doesn't work if I build a variable and search it. i.e., this works: if (!stripos($msg->Body(), 'xxxx') === false) { echo "\n found in Body()\n"; } but this doesn't (I've tried it with and without htmlentities()): $searchtext = htmlentities($msg->Sender()) . htmlentities($msg->To()) . htmlentities($msg->Cc()) . htmlentities($msg->Subject()) . htmlentities($msg->Body()); if (!stripos($searchtext, 'xxxx') === false) { echo "\nstring found!\n"; } Does anyone have any ideas? Thanks. Regards, Bruce