diff --git a/application/forms/ConfigForm.php b/application/forms/ConfigForm.php
index 1c79600b5..f3a61ee79 100644
--- a/application/forms/ConfigForm.php
+++ b/application/forms/ConfigForm.php
@@ -57,11 +57,7 @@ class ConfigForm extends Form
     public function onSuccess()
     {
         $sections = array();
-        foreach ($this->getValues() as $sectionAndPropertyName => $value) {
-            if (empty($value)) {
-                $value = null; // Causes the config writer to unset it
-            }
-
+        foreach (static::transformEmptyValuesToNull($this->getValues()) as $sectionAndPropertyName => $value) {
             list($section, $property) = explode('_', $sectionAndPropertyName, 2);
             $sections[$section][$property] = $value;
         }
@@ -137,8 +133,12 @@ class ConfigForm extends Form
      */
     public static function transformEmptyValuesToNull(array $values)
     {
-        return array_map(function ($v) {
-            return empty($v) ? null : $v;
-        }, $values);
+        array_walk($values, function (&$v) {
+            if ($v === '' || $v === false || $v === array()) {
+                $v = null;
+            }
+        });
+
+        return $values;
     }
 }
diff --git a/test/php/library/Icinga/Web/ConfigFormTest.php b/test/php/library/Icinga/Web/ConfigFormTest.php
new file mode 100644
index 000000000..dab3582ed
--- /dev/null
+++ b/test/php/library/Icinga/Web/ConfigFormTest.php
@@ -0,0 +1,91 @@
+<?php
+/* Icinga Web 2 | (c) 2017 Icinga Development Team | GPLv2+ */
+
+namespace Tests\Icinga\Web;
+
+use Icinga\Forms\ConfigForm;
+use Icinga\Test\BaseTestCase;
+
+class ConfigFormTest extends BaseTestCase
+{
+    public function testWhetherTransformEmptyValuesToNullHandlesValuesCorrectly()
+    {
+        $values = array(
+            'empty_string'      => '',
+            'example_string'    => 'this is a test',
+            'empty_array'       => array(),
+            'example_array'     => array('test1', 'test2'),
+            'zero_as_int'       => 0,
+            'one_as_int'        => 1,
+            'zero_as_string'    => '0',
+            'one_as_string'     => '1',
+            'bool_true'         => true,
+            'bool_false'        => false,
+            'null'              => null
+        );
+
+        $values = ConfigForm::transformEmptyValuesToNull($values);
+
+        $this->assertNull(
+            $values['empty_string'],
+            'ConfigForm::transformEmptyValuesToNull() does not handle empty strings correctly'
+        );
+
+        $this->assertSame(
+            'this is a test',
+            $values['example_string'],
+            'ConfigForm::transformEmptyValuesToNull() does not handle strings correctly'
+        );
+
+        $this->assertNull(
+            $values['empty_array'],
+            'ConfigForm::transformEmptyValuesToNull() does not handle empty arrays correctly'
+        );
+
+        $this->assertSame(
+            'test1',
+            $values['example_array'][0],
+            'ConfigForm::transformEmptyValuesToNull() does not handle arrays correctly'
+        );
+
+        $this->assertSame(
+            0,
+            $values['zero_as_int'],
+            'ConfigForm::transformEmptyValuesToNull() does not handle zeros correctly'
+        );
+
+        $this->assertSame(
+            1,
+            $values['one_as_int'],
+            'ConfigForm::transformEmptyValuesToNull() does not handle numbers correctly'
+        );
+
+        $this->assertSame(
+            '0',
+            $values['zero_as_string'],
+            'ConfigForm::transformEmptyValuesToNull() does not handle zeros correctly'
+        );
+
+        $this->assertSame(
+            '1',
+            $values['one_as_string'],
+            'ConfigForm::transformEmptyValuesToNull() does not handle numbers correctly'
+        );
+
+        $this->assertSame(
+            true,
+            $values['bool_true'],
+            'ConfigForm::transformEmptyValuesToNull() does not handle bool true correctly'
+        );
+
+        $this->assertNull(
+            $values['bool_false'],
+            'ConfigForm::transformEmptyValuesToNull() does not handle bool false correctly'
+        );
+
+        $this->assertNull(
+            $values['null'],
+            'ConfigForm::transformEmptyValuesToNull() does not handle null correctly'
+        );
+    }
+}