Index: branches/RC/core/kernel/processors/tag_processor.php
===================================================================
diff -u -N -r10610 -r11538
--- branches/RC/core/kernel/processors/tag_processor.php	(.../tag_processor.php)	(revision 10610)
+++ branches/RC/core/kernel/processors/tag_processor.php	(.../tag_processor.php)	(revision 11538)
@@ -74,7 +74,7 @@
 
 			return md5($k);
 		}
-		
+
 		function ProcessParsedTag($tag, $params, $prefix, $file='unknown', $line=0)
 		{
 			$Method = $tag;
@@ -85,13 +85,13 @@
 
 				$backup_prefix = $this->Prefix;
 				$backup_special = $this->Special;
-				
+
 				if ($this->Application->ConfigValue('SystemTagCache') && isset($params['cache_timeout'])) {
 					if ($res = $this->Application->CacheGet($this->FormCacheKey($tag, $params, $prefix))) {
 						return $res;
 					}
 				}
-				
+
 				$original_params = $params;
 				$flag_values = $this->PreparePostProcess($params);
 
@@ -214,16 +214,34 @@
 	 * @return string
 	 * @access public
 	 */
-	function SelectParam($params, $possible_names)
+	function SelectParam($params, $possible_names = null)
 	{
-		if (!is_array($params)) return;
-		if (!is_array($possible_names))
+		if (!isset($possible_names)) {
+			// select 1st parameter non-empty parameter value
+			$possible_names = explode(',', $params['possible_names']);
+			foreach ($possible_names as $param_name) {
+				$value = $this->Application->Parser->GetParam($param_name);
+				if ((string)$value != '') {
+					return $value;
+				}
+			}
 
-		$possible_names = explode(',', $possible_names);
-		foreach ($possible_names as $name)
-		{
+			return '';
+		}
+
+		if (!is_array($params)) {
+			// really happens?
+			return;
+		}
+
+		if (!is_array($possible_names)) {
+			$possible_names = explode(',', $possible_names);
+		}
+
+		foreach ($possible_names as $name) {
 			if( isset($params[$name]) ) return $params[$name];
 		}
+
 		return false;
 	}
 }