diff --git a/administrator/components/com_config/model/form/application.xml b/administrator/components/com_config/model/form/application.xml
index a6242254cd649..24ce1441c2a78 100644
--- a/administrator/components/com_config/model/form/application.xml
+++ b/administrator/components/com_config/model/form/application.xml
@@ -727,12 +727,14 @@
 			name="lifetime"
 			type="number"
 			min="1"
+			step="1"
 			default="15"
 			label="COM_CONFIG_FIELD_SESSION_TIME_LABEL"
 			description="COM_CONFIG_FIELD_SESSION_TIME_DESC"
 			required="true"
 			filter="integer"
 			validate="number"
+			class="validate-range"
 			size="6" />
 
 		<field
diff --git a/administrator/components/com_config/view/application/html.php b/administrator/components/com_config/view/application/html.php
index 84588a2516e11..9222ed38d3e45 100644
--- a/administrator/components/com_config/view/application/html.php
+++ b/administrator/components/com_config/view/application/html.php
@@ -48,6 +48,9 @@ public function render()
 			return false;
 		}
 
+		JHtml::_('behavior.formvalidator');
+		JHtml::script('media/com_config/js/validate-number.js');
+
 		// Bind data
 		if ($form && $data)
 		{
diff --git a/media/com_config/js/validate-number-uncompressed.js b/media/com_config/js/validate-number-uncompressed.js
new file mode 100644
index 0000000000000..232e23f3502ac
--- /dev/null
+++ b/media/com_config/js/validate-number-uncompressed.js
@@ -0,0 +1,24 @@
+;(function($){
+	$(function(){
+		document.formvalidator.setHandler('range', function(value, element){
+			
+			var min  = parseFloat(element.prop('min')),
+				max  = parseFloat(element.prop('max')),
+				step = parseFloat(element.prop('step'));
+
+			if(!isNaN(min) && min > value){
+				return false;
+			}
+
+			if(!isNaN(max) && max < value){
+				return false;
+			}
+
+			if(!isNaN(step) && value % step !== 0){
+				return false;
+			}
+
+			return true;
+		});
+	});
+})(jQuery);
diff --git a/media/com_config/js/validate-number.js b/media/com_config/js/validate-number.js
new file mode 100644
index 0000000000000..3c9d42dad9a97
--- /dev/null
+++ b/media/com_config/js/validate-number.js
@@ -0,0 +1 @@
+(function(e){e(function(){document.formvalidator.setHandler("range",function(e,t){var n=parseFloat(t.prop("min")),r=parseFloat(t.prop("max")),i=parseFloat(t.prop("step"));return!isNaN(n)&&n>e?!1:!isNaN(r)&&r<e?!1:!isNaN(i)&&e%i!==0?!1:!0})})})(jQuery);
\ No newline at end of file