--- a/src/pyams_skin/resources/js/myams.js	Tue Sep 18 16:20:27 2018 +0200
+++ b/src/pyams_skin/resources/js/myams.js	Thu Sep 20 13:46:52 2018 +0200
@@ -1756,11 +1756,7 @@
 									}
 									if (formDataCallback) {
 										var veto = {};
-										if (typeof(formDataCallback) === 'function') {
-											formData = formDataCallback.call(form, veto);
-										} else {
-											formData = ams.executeFunctionByName(formDataCallback, form, veto);
-										}
+										formData = ams.executeFunctionByName(formDataCallback, form, veto);
 										if (veto.veto) {
 											button = form.data('ams-submit-button');
 											if (button) {