Shell exec doesn't execute

Hi folks,

thought I pop in and ask a little question

so here's the problem:

$query = "scp liesmich.txt [email protected]:/home/samba/$_POST[share]/$dir/";
$result = shell_exec($query);
$query2 = "ln -v -s /backup/data/keto-samba/current/$_POST[share]/$dir /backup/archive/AUTOARCHIVE/$_POST[share]_$dir";
echo $query2;
$result2 = shell_exec($query2);
echo "Result: $result2";

Odd: $result is executed just fine, $result2 simply does nothing. No error, no response, simply zip?