I can log into and read my emails in the gmail standard view, but as soon as I do something that requires an update to gmail (opening an unread mail, replying ,archiving, deleting etc.), then I get an error message in the heading "sorry there is a problem in the system #500, will try again in xx seconds".

If I select use basic html, it works.
This is not a big problem, because all the functions I normally use in gmail are available in the basic interface. But I really want to know if this is a limitation in OWB 1.7, or if it is just my setup. Maybe I have some wrong settings or something.

It works just fine, but you need to enable the new cookie system (which is default now, though).
So go to OWB settings->network and enable "experimental cookies".

Thanks for the quick reply. Yes that fixed it :)
I was using the "setenv OWB_EXPERIMENTAL_COOKIES 1" in user-startup so I thought it was enabled already.
Apearently I did not read the updated readme well enaugh.

Just to be sure, this means that I can delete that entry from user-startup, right?

Yes, that ENV variable was moved to regular settings, so it's not needed anymore.

Oh, and just for information, there was no need to put that in user-startup before, you could just have used setenv save <blah> to make the change reset-proof (save option saves to envarc: as well).