Google Appspot: how to customize or change language of the Google Accounts Sign In page

I'm creating a Google Appspot app. If a user is not logged on, they are redirected to the standard sign in page:

resp.sendRedirect(userService.createLoginURL(req.getRequestURI()));         

The page URI parameters are:

https://www.google.com/accounts/ServiceLogin?
service=ah&continue=...&ltmpl=gm&ahname=Your+App+Name&sig=...

Is there a way to customize the sign in page to some extent, while still using Google Accounts?

Most importantly, is it possible to change th开发者_运维百科e language of the page (since my website is not in English)?

Edit: if I visit any Google site in a specific language (e.g. http://www.google.com/webhp?hl=th, then the login page would be in that language (perhaps Google sets a cookie?). However, ServiceLogin script seems not to support the hl= parameter.

I don't think you can change this right now. That said, it's possible that Google will serve the sign up page in whatever language is default in the user's browser. They might be doing that already, if I'm not mistaken.