I'd be delighted if somebody could explain what the hell's going on here. I switched mail for the holdenweb.com domain to run through Google's Gmail for Domains service. Things had been going quite nicely, and the spam levels had reduced amazingly without me having to apply any external filtering (which makes me wonder just exactly why Google Groups is so clogged up with the output of asshole spammers, but that's another post).
Recently I have started to receive replies to emails sent out from my holdenweb.com account in the Gmail mailbox I have used for years. At first I though this might be Thunderbird (or me) getting my email accounts and personalities mixed up, but it appears this isn't the case. Here's a test message I sent to myself as an experiment, as it looks in my Sent folder:
So it definitely looks as though it went out from holdenweb.com. And here's the same message as it arrived in my Inbox:
So it goes out from my holdenweb.com address, and arrived at the recipient from my gmail.com address. That's pretty evil, Google - or is there some obvious way I am shooting myself in the foot? It's making my mail conversations pretty hard to track right now.