Or edit it your source: 
 
Index: /TrunK/L2JBrasil_CORE/java/com/it/br/Config.java
===================================================================
--- /TrunK/L2JBrasil_CORE/java/com/it/br/Config.java (revision 673)
+++ /TrunK/L2JBrasil_CORE/java/com/it/br/Config.java (revision 674)
@@ -933,4 +933,5 @@
    public static int       DUEL_SPAWN_Y;  
    public static int       DUEL_SPAWN_Z; 
+   public static int       ALT_BUFF_TIME;
    public static int       NOBLE_CUSTOM_ITEM_ID; 
    public static boolean   ALLOW_NOBLE_CUSTOM_ITEM; 
@@ -1282,5 +1283,5 @@
               DUEL_SPAWN_Y    = Integer.parseInt(L2JBrasil.getProperty("PartyDuelSpawnY", "46710"));  
               DUEL_SPAWN_Z    = Integer.parseInt(L2JBrasil.getProperty("PartyDuelSpawnZ", "-3413"));
-
+              ALT_BUFF_TIME   = Integer.parseInt(L2JBrasil.getProperty("AltBuffTime", "1"));
               ALT_NEW_SPAWN   = Boolean.parseBoolean(L2JBrasil.getProperty("Customspawn", "False"));  
               ALT_NEW_SPAWN_X = Integer.parseInt(L2JBrasil.getProperty("CustomSpawnX", ""));  
Index: /TrunK/L2JBrasil_CORE/java/com/it/br/gameserver/model/L2Skill.java
===================================================================
--- /TrunK/L2JBrasil_CORE/java/com/it/br/gameserver/model/L2Skill.java (revision 650)
+++ /TrunK/L2JBrasil_CORE/java/com/it/br/gameserver/model/L2Skill.java (revision 674)
@@ -27,4 +27,6 @@
import javolution.text.TextBuilder;
import javolution.util.FastList;
+
+import com.it.br.Config;
import com.it.br.gameserver.GeoData;
import com.it.br.gameserver.datatables.HeroSkillTable;
@@ -523,5 +525,5 @@
         //_skillInterruptTime = set.getInteger("hitTime", _hitTime / 2);
         _reuseDelay = set.getInteger("reuseDelay", 0);
-        _buffDuration = set.getInteger("buffDuration", 0);
+        _buffDuration = set.getInteger("buffDuration", 0) * Config.ALT_BUFF_TIME;
         _skillRadius = set.getInteger("skillRadius", 80);
Index: /TrunK/L2JBrasil_CORE/config/L2JBrasil.properties
===================================================================
--- /TrunK/L2JBrasil_CORE/config/L2JBrasil.properties (revision 670)
+++ /TrunK/L2JBrasil_CORE/config/L2JBrasil.properties (revision 674)
@@ -46,4 +46,7 @@
# Retail: 300
MaxMCritRate = 300
+
+# Buff time rate
+AltBuffTime = 1
# Heavy Equipment Restriction