--- a/playground/jsonld.js	Mon May 07 15:39:13 2012 -0400
+++ b/playground/jsonld.js	Mon May 07 15:52:11 2012 -0400
@@ -3720,7 +3720,7 @@
       // array @context
       if(_isArray(ctx)) {
         var length = ctx.length;
-        for(var i = 0; i < ctx.length; ++i) {
+        for(var i = 0; i < length; ++i) {
           var _ctx = ctx[i];
           if(_isString(_ctx)) {
             // replace w/@context if requested