diff --git a/src/main/java/de/infinimotion/persistence/processor/FilterQuery.java b/src/main/java/de/infinimotion/persistence/processor/FilterQuery.java
index 5b5de7a..663018e 100644
--- a/src/main/java/de/infinimotion/persistence/processor/FilterQuery.java
+++ b/src/main/java/de/infinimotion/persistence/processor/FilterQuery.java
@@ -31,10 +31,12 @@ public class FilterQuery implements GenericFilterQuery {
                 String[] pathSplit = split[1].split("\\.");
                 Predicate predicate = switch (split[2]) {
                     case "int" -> filterGeneric(cb, root, pathSplit, split[0], Integer.parseInt(split[3]));
-                    case "date" -> filterGeneric(cb, root, pathSplit, split[0], Date.from(Instant.parse(split[3])));
+                    case "date" ->
+                            filterGeneric(cb, root, pathSplit, split[0], Date.from(Instant.parse(split[3].endsWith("Z") ? split[3] : split[3] + "Z")));
                     case "localdate" -> filterGeneric(cb, root, pathSplit, split[0], LocalDate.parse(split[3]));
                     case "localtime" -> filterGeneric(cb, root, pathSplit, split[0], LocalTime.parse(split[3]));
-                    default -> filterGeneric(cb, root, pathSplit, split[0], split[3]);
+                    case "string" -> filterGeneric(cb, root, pathSplit, split[0], split[3]);
+                    default -> throw new IllegalArgumentException("unknown filter datatype: " + split[2]);
                 };
                 predicates.add(predicate);
             }
@@ -59,7 +61,7 @@ public class FilterQuery implements GenericFilterQuery {
             case "le" -> cb.lessThanOrEqualTo(path, value);
             case "null" -> cb.isNull(path);
             case "nn" -> cb.isNotNull(path);
-            default -> throw new IllegalArgumentException("unknown filter: " + operator);
+            default -> throw new IllegalArgumentException("unknown filter operator: " + operator);
         };
     }