diff --git a/lib/transcoder.js b/lib/transcoder.js
index c8f2550..9d9bd25 100644
--- a/lib/transcoder.js
+++ b/lib/transcoder.js
@@ -401,7 +401,7 @@ function Transcoder(source) {
 		if (value !== undefined) {
 			args.push(value);
 		}
-		this.args[key] = args;
+		this.args[Object.keys(this.args).length] = args;
 		return this;
 	};