ip deny not working

hi. i have a prob on a site i host . i have put deny from then the ip number in htaccess .but whoever it is or what ever it is . is still accessing the site .how can this be .

Either

You did it wrong
They have a dynamic ip
They have a proxy
They are accessing it from a different location

IP based blocking is not very reliable in general, simply because it's so easy for most people to get a new IP.

done some searching and found some help against robots but i get an error on this line

$msg = "A bad robot hit $_SERVER['REQUEST_URI'] $datum \n";

this is the error
Parse error: syntax error, unexpected T_ENCAPSED_AND_WHITESPACE, expecting T_STRING or T_VARIABLE or T_NUM_STRING in /home/public_html/bot-trap/index.php on line 29

Many apache servers differs from each other. You should check it first.