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I import the mail from the two @gmail.com accounts into my main domain account, in a specific subfolder. I do this to be able to see all my incoming mail in ONE account. Why? Because at work I can only log into my mail via webmail. By using the browser, I can only log into one Gmail account at a time. By logging into my main account and having it import the mail of both @gmail.com accouts, I have a nice overview of ALL my new mail, on one screen. (my webmail screen is always open at work)

For the import I use the "check mail from other accounts using POP3" option that is built into Gmail. It's for this reason I have POP3 enabled on the @gmail.com accounts. If I wouldn't need the import of the mail into the main account, I would disable POP3 entirely and only use IMAP (now they are both enabled).

,... with Android, and its much better Gmail integration, I saw the opportunity to not only configure only the main email account, but also both @gmail accounts. (the Android client is better at this than iOS's email client is). Another reason: Android also allows for push mail with Gmail (which the iPhone client did not, not anymore anyway), so I figured I'd configure all three accounts this time.

This works very well, EXCEPT for the fact that mail read on my Android phone does NOT show up as "read" on my desktop's Thunderbird or the webmail app. It's like the Android app doesn't tell the mail server the mail was read.

I cannot find any setting to configure this. I'm sure my sync settings are on (all the rest works fine, calendar synching etc...)
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