Index: src/main/java/org/apache/maven/archiva/web/validator/CronExpressionValidator.java
===================================================================
--- src/main/java/org/apache/maven/archiva/web/validator/CronExpressionValidator.java	(revision 0)
+++ src/main/java/org/apache/maven/archiva/web/validator/CronExpressionValidator.java	(revision 0)
@@ -0,0 +1,48 @@
+package org.apache.maven.archiva.web.validator;
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import com.opensymphony.xwork.validator.ValidationException;
+import com.opensymphony.xwork.validator.ValidatorContext;
+import com.opensymphony.xwork.validator.validators.FieldValidatorSupport;
+
+
+/**
+ * Reused from Continuum crontab validator
+ *
+ */
+public class CronExpressionValidator extends FieldValidatorSupport
+{
+
+    public void validate( Object obj )
+        throws ValidationException
+    {
+    	String cron = (String) getFieldValue( "cron", obj );
+    	
+        org.codehaus.plexus.scheduler.CronExpressionValidator cronExpressionValidator=
+        	new org.codehaus.plexus.scheduler.CronExpressionValidator();
+        
+        ValidatorContext ctxt = getValidatorContext();
+        if ( !cronExpressionValidator.validate( String.valueOf(cron) ) )
+        {
+        	ctxt.addActionError( "Invalid cron expression value(s)" );
+            return;
+        }
+    }
+}
\ No newline at end of file
Index: src/main/resources/validators.xml
===================================================================
--- src/main/resources/validators.xml	(revision 680931)
+++ src/main/resources/validators.xml	(working copy)
@@ -34,5 +34,6 @@
   <validator name="regex" class="com.opensymphony.xwork.validator.validators.RegexFieldValidator"/>
   <validator name="interval" class="org.apache.maven.archiva.web.validator.IntervalValidator"/>
   <validator name="syncedrepo" class="org.apache.maven.archiva.web.validator.SyncedRepositoryValidator"/>
+  <validator name="crontab" class="org.apache.maven.archiva.web.validator.CronExpressionValidator"/>
 </validators>
 
Index: src/main/resources/org/apache/maven/archiva/web/action/admin/database/DatabaseAction-validation.xml
===================================================================
--- src/main/resources/org/apache/maven/archiva/web/action/admin/database/DatabaseAction-validation.xml	(revision 0)
+++ src/main/resources/org/apache/maven/archiva/web/action/admin/database/DatabaseAction-validation.xml	(revision 0)
@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="ISO-8859-1"?>
+<!--
+  ~ Licensed to the Apache Software Foundation (ASF) under one
+  ~ or more contributor license agreements.  See the NOTICE file
+  ~ distributed with this work for additional information
+  ~ regarding copyright ownership.  The ASF licenses this file
+  ~ to you under the Apache License, Version 2.0 (the
+  ~ "License"); you may not use this file except in compliance
+  ~ with the License.  You may obtain a copy of the License at
+  ~
+  ~   http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing,
+  ~ software distributed under the License is distributed on an
+  ~ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+  ~ KIND, either express or implied.  See the License for the
+  ~ specific language governing permissions and limitations
+  ~ under the License.
+  -->
+
+<!DOCTYPE validators PUBLIC "-//OpenSymphony Group//XWork Validator 1.0.2//EN"
+    "http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd">
+<validators>
+  <field name="cron">
+    <field-validator type="requiredstring">
+      <message>You must enter a cron expression.</message>
+    </field-validator>
+    <field-validator type="crontab">
+      <message>Invalid cron expression value(s).</message>
+    </field-validator>
+  </field>
+</validators>
\ No newline at end of file