calling mogrify from php

Hi, i'm trying to run mogrify from php in order to create thumbnails. The full mogrify command is in a small shellscript and executes fine when called from the shell. <?php echo "$userfile[0], $userfile_name[0]<br>"; echo "$userfile[1], $userfile_name[1]<br>"; copy ($userfile[0], "/gabriel/html/mogrify/$userfile_name[0]"); copy ($userfile[1], "/gabriel/html/mogrify/$userfile_name[1]"); exec("/path-to-script/mogrify_640x480_sharpen"); ?> By some reason it doesn't work with the above code- i've no clue why. Thanks for any hints! Gabriel