ReaLs,
Вот:моя переделка кода...
$var = preg_replace('#\[RT\](.*?)\[/RT\]#si', '<object width="380" height="400">
<param name="movie" value="http://video.rutube.ru/\1?rel=1&color1=34c924&
color2=3caa3c&border=1&fs=1">
</param><param name="wmode" value="window">
</param><param name="allowFullScreen" value="true">
</param><embed src="http://video.rutube.ru/\1?rel=1&color1=34c924&color2=3caa3c&border=1&fs=1"
type="application/x-shockwave-flash"
wmode="window"
width="380"
height="400"
allowFullScreen="true" >
</embed></object>', $var);