diff --git a/index.js b/index.js
index 88b1983..099603f 100644
--- a/index.js
+++ b/index.js
@@ -408,7 +408,7 @@ function adapter(uri, opts){
         return;
       }
 
-      numsub = numsub[1];
+      numsub = parseInt(numsub[1], 10);
 
       var request = JSON.stringify({
         requestid : requestid,