diff --git a/src/cfgparse.y b/src/cfgparse.y
index bcd7d20c..c3efb063 100644
--- a/src/cfgparse.y
+++ b/src/cfgparse.y
@@ -1057,7 +1057,8 @@ word_or_number:
     ;
 
 duration:
-    NUMBER TOK_TIME_MS { sasprintf(&$$, "%d", $1); }
+    NUMBER { sasprintf(&$$, "%d", $1); }
+    | NUMBER TOK_TIME_MS { sasprintf(&$$, "%d", $1); }
     ;
 
 mode: