diff -r 91d1fc2a3a14 -r 33b6843fdf8a src/main/java/de/uapcore/lightpit/AbstractLightPITServlet.java
--- a/src/main/java/de/uapcore/lightpit/AbstractLightPITServlet.java	Fri May 22 17:26:27 2020 +0200
+++ b/src/main/java/de/uapcore/lightpit/AbstractLightPITServlet.java	Fri May 22 21:23:57 2020 +0200
@@ -295,6 +295,13 @@
         final String paramValue = req.getParameter(name);
         if (paramValue == null) return Optional.empty();
         if (clazz.equals(String.class)) return Optional.of((T) paramValue);
+        if (java.sql.Date.class.isAssignableFrom(clazz)) {
+            try {
+                return Optional.of((T)java.sql.Date.valueOf(paramValue));
+            } catch (IllegalArgumentException ex) {
+                return Optional.empty();
+            }
+        }
         try {
             final Constructor<T> ctor = clazz.getConstructor(String.class);
             return Optional.of(ctor.newInstance(paramValue));