Thomas and Boris thanks for your comments. Here are a few more details.
It is very hard to test, because it does not happen for me. I have even trotted my laptop around to various cafes / wireless environments trying to provoke the problem, but I have not yet experienced the problem. It is not SOP, because the web page and the web server are coming from the same domain + server. It is (seemingly!) random. I have talked to two users to verify this. When an RPC call fails (e.g writing a record), if they try the same call a few seconds later, it might succeed. One of the apps subject to this problem has been in production since 2008. This problem has appeared only recently. I think the first time a user wrote in about was in Dec 2011, and since I could not replicate what he was talking about, I attempted to dismiss it as related to his strange bad internet connection. Since then many users have reported it. There have been certain days when it seem to happen a lot. I have some tried some weird stuff, like iterating on the RPC call while it is failing (try - fail - wait - try again ... 4 times). I can't tell if this ever does any good, but from what the user told me yesterday, sometimes it goes through 4 tries without succeeding. -- You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group. To view this discussion on the web visit https://groups.google.com/d/msg/google-web-toolkit/-/hSP_1G1ummcJ. To post to this group, send email to google-web-toolkit@googlegroups.com. To unsubscribe from this group, send email to google-web-toolkit+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-web-toolkit?hl=en.