Q:

cannot transfer date after switching from sdk 1.9.11 to 1.9.12

I have an application accessing Google cloud endpoints on a Java appengine application from javascript. when using standard javascript "new Date()" for dates and using gapi, it stops working for 1.9.12 with an error in the server rfc3339 parser because the date transmitted is indeed not rfc3339. 
Is this a known problem? Or should we now somehow transform all dates on the js side to some rfc3339 format instead of using the date class? The release notes state no changes from 1.9.11 to 1.9.12 for Java.
I just tested in the dev environment, not on production. Adding a .toISOString() solves the problem, but is necessary for every js date used.

A:

I'm glad to hear that toISOString() solved it. Perhaps you might want to go to the public issue tracker for the app engine and file an issue relating to the SDK release notes, if you have observed this change?
One thing you could do is to look into ApiTransformer's - these define how data is transformed when coming to your API. You could have any class that accepts Dates (however they end up being serialized) to convert them to rfc3339 and then use this to build a native java Date? 
Honestly, I think you should even try to use SDK 1.9.17 and see if it works there.
Also, finally, I wonder if this thread will help you?

