within the if statement do this
<?php
if ($clan_logo ==""){
$logo_location = "http://www.someurl_to_logo.com/".$clan_logo;
$fp = @fopen($logo_location,"r");
if ($fp){
?>
<img border='0' src='<?=$clan_logo?>' width='<?=$clan_logo_width?>' height='<?=$clan_logo_height?>'>
<?php
}else{
print "sorry, no image is available";
}
fclose($fp);
} else {
?>
Sorry, no logo has been specified.
<?php
}
?>
this might work, see if the path to the logo is proper