[thelist] getting visitor's local time or time zone

[Joel D Canfield]

we've moved my client's forum to Invision's IP.Board; one issue I can't
get my head around.

when a user is logged in, the board gets their local time zone and DST
setting from their profile. Invision's excellent support staff tell me
that the reason the time is off when you're not logged in is because the
board can't tell where you are, what your local time zone is and whether
or not DST is in effect or is even used.

I make these assumptions about time and dates and computers, so I'm
probably completely wrong, but I had assumed that, even in the safe
sandbox of a browser, the website would know where I was (based, of
course, just on IP address since that's likely all it knows, and is of
course not entirely accurate itself) and could determine all the above.

where's the flaw in my reasoning, and, probably more important, how can
I explain this to my client so he gets that it's a technical issue we
can't resolve, not a flaw with the forum?

thanks

--
Joel D Canfield
Joel at BizBa6.com