diff --git a/scripts/postfixadmin-cli.php b/scripts/postfixadmin-cli.php
index 782c01a8..7b609442 100644
--- a/scripts/postfixadmin-cli.php
+++ b/scripts/postfixadmin-cli.php
@@ -319,11 +319,11 @@ class PostfixAdmin {
     public function parseParams($params) {
         $count = count($params);
         for ($i = 0; $i < $count; $i++) {
-            if ($params[$i] != '' && $params[$i]{0} === '-' && $params[$i] != '-1') {
+            if ($params[$i] != '' && $params[$i][0] === '-' && $params[$i] != '-1') {
                 $key = substr($params[$i], 1);
                 if (isset($params[$i+1])) {
                     # TODO: ideally we should know if a parameter can / must have a value instead of whitelisting known valid values starting with '-' (probably only bool doesn't need a value)
-                    if ($params[$i+1]{0} === '-' && $params[$i+1] != '-1') {
+                    if ($params[$i+1][0] === '-' && $params[$i+1] != '-1') {
                         $this->params[$key] = true;
                     } else {
                         $this->params[$key] = $params[$i+1];