diff --git a/code/GridFieldAddNewMultiClassHandler.php b/code/GridFieldAddNewMultiClassHandler.php
index cf99b5b..8eb41d0 100644
--- a/code/GridFieldAddNewMultiClassHandler.php
+++ b/code/GridFieldAddNewMultiClassHandler.php
@@ -9,9 +9,16 @@ class GridFieldAddNewMultiClassHandler extends GridFieldDetailForm_ItemRequest {
 			return parent::Link($action);
 		} else {
 			return Controller::join_links(
-				$this->gridField->Link(), 'add-multi-class', get_class($this->record)
+				$this->gridField->Link(), 'add-multi-class', $this->sanitiseClassName(get_class($this->record))
 			);
 		}
 	}
 
+	/**
+     * Sanitise a model class' name for inclusion in a link
+     * @return string
+     */
+    protected function sanitiseClassName($class) {
+        return str_replace('\\', '-', $class);
+    }
 }