diff --git a/framework/base/Component.php b/framework/base/Component.php
index 63e4b48..62d08ee 100644
--- a/framework/base/Component.php
+++ b/framework/base/Component.php
@@ -174,7 +174,7 @@ class Component extends Object
 				}
 			}
 		}
-		throw new InvalidCallException('Unsetting read-only property: ' . get_class($this) . '.' . $name);
+		throw new InvalidCallException('Unsetting an unknown or read-only property: ' . get_class($this) . '.' . $name);
 	}
 
 	/**