Comment 3 for bug 37138

> I'm afraid there's no en_FI locale

In Debian-based distributions, you have separate settings for language, measurement system, time and money: locales.

For example, here is the printout of 'locale' in a Debian system (just an example, this is not a good config for me):
$ locale
LANG=en_US
LANGUAGE=en_FI:en_US:en_GB:en
LC_CTYPE="en_US"
LC_NUMERIC="en_US"
LC_TIME="en_US"
LC_COLLATE="en_US"
LC_MONETARY="en_US"
LC_MESSAGES="en_US"
LC_PAPER="en_US"
LC_NAME="en_US"
LC_ADDRESS="en_US"
LC_TELEPHONE="en_US"
LC_MEASUREMENT="en_US"
LC_IDENTIFICATION="en_US"
LC_ALL=en_US

With location Finland, installer should set:
Measurement: metric (SI) system
Paper: A4
Monetary unit: EUR (euro)
Numeric system: Use comma as decimal separator, use space to separate thousands (the SI way) 126 023,15
Time format: Finnish, 10.4.2006

In addition to locales, installer should set default answer to keyboard question to "Finnish".