diff --git a/modules/core/lib/Auth/Process/AttributeAlter.php b/modules/core/lib/Auth/Process/AttributeAlter.php
index 4760c04ba11d6a6e8bff4e3ffd26f2734fd80858..c9a2acfd770848ef80e7e0f5d397ac0b13e170d1 100644
--- a/modules/core/lib/Auth/Process/AttributeAlter.php
+++ b/modules/core/lib/Auth/Process/AttributeAlter.php
@@ -57,7 +57,7 @@ class sspmod_core_Auth_Process_AttributeAlter extends SimpleSAML_Auth_Processing
                 // check if this is an option
                 if($value === '%replace') {
                     $this->replace = TRUE;
-                } elseif ($value == '%remove') {
+                } elseif ($value === '%remove') {
                     $this->remove = TRUE;
                 } else {
                     throw new SimpleSAML_Error_Exception('Unknown flag : ' . var_export($value, TRUE));
@@ -65,11 +65,6 @@ class sspmod_core_Auth_Process_AttributeAlter extends SimpleSAML_Auth_Processing
                 continue;
             }
 
-            // Unknown flag
-            if (!is_string($name)) {
-                throw new SimpleSAML_Error_Exception('Unknown flag : ' . var_export($name, TRUE));
-            }
-
             // Set pattern
             if ($name === 'pattern') {
                 $this->pattern = $value;