diff --git a/CHANGES b/CHANGES
index 8f359e37..465e7c63 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,7 +1,10 @@
 
-26 Jan 2010 - trunk
+27 Jan 2010 - trunk
 -------------------
 
+ * Added DURATION, which contains the time ellapsed since the beginning
+   of the current transaction, in milliseconds. [Ivan Ristic]
+
  * Adjusted phase 5 to execute just prior to mod_log_config. This should
    allow phase 5 rules to to implement conditional logging, as well as
    pave support for allowing access to all ModSecurity variables from
diff --git a/apache2/re_variables.c b/apache2/re_variables.c
index 46705e6d..878bba5a 100644
--- a/apache2/re_variables.c
+++ b/apache2/re_variables.c
@@ -1426,6 +1426,23 @@ static int var_urlencoded_error_generate(modsec_rec *msr, msre_var *var, msre_ru
     }
 }
 
+/* DURATION */
+
+static int var_duration_generate(modsec_rec *msr, msre_var *var, msre_rule *rule,
+    apr_table_t *vartab, apr_pool_t *mptmp)
+{
+    msre_var *rvar = NULL;
+
+    rvar = apr_pmemdup(mptmp, var, sizeof(msre_var));
+    rvar->value = apr_psprintf(mptmp, "%" APR_TIME_T_FMT,
+        (apr_time_msec(apr_time_now() - msr->r->request_time)));
+    rvar->value_len = strlen(rvar->value);
+    
+    apr_table_addn(vartab, rvar->name, (void *)rvar);
+
+    return 1;
+}
+
 /* TIME */
 
 static int var_time_generate(modsec_rec *msr, msre_var *var, msre_rule *rule,
@@ -3017,6 +3034,17 @@ void msre_engine_register_default_variables(msre_engine *engine) {
         VAR_DONT_CACHE, /* dynamic */
         PHASE_RESPONSE_HEADERS
     );
+    
+    /* DURATION */
+    msre_engine_variable_register(engine,
+        "DURATION",
+        VAR_SIMPLE,
+        0, 0,
+        NULL,
+        var_duration_generate,
+        VAR_DONT_CACHE, /* dynamic */
+        PHASE_REQUEST_HEADERS
+    );
 
     /* TIME */
     msre_engine_variable_register(engine,