[Dovecot] INTERNALDATE call, timezone randomly changes

[Guy]

Hi guys,

I've run into an odd little problem. We use SquirrelMail as the basis
for our webmail. Recently I've had a user complaining that the
"Received" time on mail in the Sent folder has changed between logins.
The change is always been by +1 hours or -5 hours. While checking, our
developer had a time changed by +2 hours. On refresh it changed back.
He poked through the code and it looks like SquirrelMail gets the
received date via an IMAP command:
A003 FETCH 1:10 (INTERNALDATE FLAGS BODY.PEEK[HEADER.FIELDS (To
Content-Type Subject Date)])

I'm running dovecot 1.1.6, and I'm wondering how that function gets
the date and time? If I can isolate the source of the timezone I can
try and correct it. The server time shown by "date" is correct and
/etc/localtime is /usr/share/zoneinfo/Europe/London (which is correct
- I've also se the timezone in /etc/conf.d/clock is set to
"Europe/London" now), so I'm wondering where else the information
could be coming from?

Thanks for any information you can give me to help isolate the problem.
Guy

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