I have a question about the behavior of Gmail IMAP when using the default Email client on N900. I have set up everything and can send and receive emails. But the "delete" behavior is kind of strange.

Deleting from Inbox moves the message to All Mail (this is normal, just like Outlook - similar to Archive on Webmail). But deleting from All Mail does whatever god knows to the message. After I delete a message from All Mail on N900, it disappears from the folder on N900, and Outlook on my computer marks it as delete (crossed out) but I can't purge it (to delete it permanently). Manual sync doesn't help. The only way is to login Webmail and delete it from there.

Anyone can confirm this behavior and has any solution? TIA

Make sure to add the advanced imap controls lab in gmail then check settings. There are various different behaviours for delete to be controlled.

Yeah, I checked that also. I left it so that it requires manual purging to delete messages for real. So far, it has worked out with outlook.