Video m4v don't work with my Iphone & iPad

Hello,
I have 1.5TB of video format m4v,
but none of them works with my iPhone

I change /flash/modules/video/get_mobile.php from

$sFile = "files/" . $sId . ".m4v";

smartReadFile($sFile, $sFile, "video/m4v");

and I still have nothing,
yet the m4v format is forIphone and Mp4 too

how to play the video?

I've avenced, I do this code but don't work

I do not understad

<?php if(eregi('(iphone)|(ipod)',$_SERVER['HTTP_USER_AGENT'])){ ?>
<video><source src="/flash/modules/video/files/__fileID__.m4v" type="video/mp4"></video>
<?php }else{ ?>
__file__
<?php } ?>