diff --git a/entity/Task_entity/Task_entity.aod b/entity/Task_entity/Task_entity.aod
index 6fc3eb7145cf3cd79f022332a86a248c16e65d75..731bf761e48acda1a33f229646e839a82b4c903e 100644
--- a/entity/Task_entity/Task_entity.aod
+++ b/entity/Task_entity/Task_entity.aod
@@ -5,6 +5,7 @@
   <documentation>%aditoprj%/entity/Task_entity/documentation.adoc</documentation>
   <title>Task</title>
   <afterUiInit>%aditoprj%/entity/Task_entity/afterUiInit.js</afterUiInit>
+  <onValidation>%aditoprj%/entity/Task_entity/onValidation.js</onValidation>
   <iconId>VAADIN:TASKS</iconId>
   <iconIdProcess>%aditoprj%/entity/Task_entity/iconIdProcess.js</iconIdProcess>
   <titlePlural>Tasks</titlePlural>
@@ -73,7 +74,6 @@
       <inputFormat>dd.MM.yyyy HH:mm</inputFormat>
       <groupable v="true" />
       <valueProcess>%aditoprj%/entity/Task_entity/entityfields/start_date/valueProcess.js</valueProcess>
-      <onValidation>%aditoprj%/entity/Task_entity/entityfields/start_date/onValidation.js</onValidation>
     </entityField>
     <entityField>
       <name>MATURITY_DATE</name>
@@ -83,7 +83,6 @@
       <outputFormat>dd.MM.yyyy HH:mm</outputFormat>
       <inputFormat>dd.MM.yyyy HH:mm</inputFormat>
       <valueProcess>%aditoprj%/entity/Task_entity/entityfields/maturity_date/valueProcess.js</valueProcess>
-      <onValidation>%aditoprj%/entity/Task_entity/entityfields/maturity_date/onValidation.js</onValidation>
     </entityField>
     <entityField>
       <name>TYPE</name>
diff --git a/entity/Task_entity/entityfields/maturity_date/onValidation.js b/entity/Task_entity/entityfields/maturity_date/onValidation.js
deleted file mode 100644
index dec89edbf15b366b3ac13922619e585f8c1a0ab3..0000000000000000000000000000000000000000
--- a/entity/Task_entity/entityfields/maturity_date/onValidation.js
+++ /dev/null
@@ -1,9 +0,0 @@
-import("system.result");
-import("system.vars");
-import("Date_lib");
-import("Entity_lib");
-
-var cEnd = ProcessHandlingUtils.getOnValidationValue(vars.get("$field.MATURITY_DATE"));
-
-if (DateUtils.validateBeginnBeforeEnd(vars.get("$field.START_DATE"), cEnd) === false)
-    result.string(DateUtils.getValidationFailString());
\ No newline at end of file
diff --git a/entity/Task_entity/entityfields/start_date/onValidation.js b/entity/Task_entity/entityfields/start_date/onValidation.js
deleted file mode 100644
index afad30d552400a5cb23f3c668ef9514209a8e7b4..0000000000000000000000000000000000000000
--- a/entity/Task_entity/entityfields/start_date/onValidation.js
+++ /dev/null
@@ -1,10 +0,0 @@
-import("system.neon");
-import("system.result");
-import("system.vars");
-import("Date_lib");
-import("Entity_lib");
-
-var cStart = ProcessHandlingUtils.getOnValidationValue(vars.get("$field.START_DATE"));
-
-if (DateUtils.validateBeginnBeforeEnd(cStart, vars.get("$field.MATURITY_DATE")) === false)
-    result.string(DateUtils.getValidationFailString());
\ No newline at end of file
diff --git a/entity/Task_entity/onValidation.js b/entity/Task_entity/onValidation.js
new file mode 100644
index 0000000000000000000000000000000000000000..497ca1efd91611cef6aad4c22a686c717b5a6e61
--- /dev/null
+++ b/entity/Task_entity/onValidation.js
@@ -0,0 +1,9 @@
+import("system.result");
+import("Date_lib");
+import("system.vars");
+
+var startDate = vars.get("$field.START_DATE");
+var endDate = vars.get("$field.MATURITY_DATE");
+
+if (!DateUtils.validateBeginnBeforeEnd(startDate, endDate))
+    result.string(DateUtils.getValidationFailString());
\ No newline at end of file