You could check for the locale and set this when configuring, I'm not sure it is worth it though, on my box, LANG is set to LANG=en_US.UTF-8 so I could take that and infer "en" from it.
Looking at my spam I don't seem to get a lot of non-english Spam, so I'm not sure this would help me.
ok_locales xx [ yy zz ... ] (default: all)
This option is used to specify which locales are considered OK for incoming mail. Mail using the character sets that are allowed by this option will not be marked as possibly being spam in a foreign language.
If you receive lots of spam in foreign languages, and never get any non-spam in these languages, this may help. Note that all ISO-8859-* character sets, and Windows code page character sets, are always permitted by default.
Set this to all to allow all character sets. This is the default.
The rules CHARSET_FARAWAY, CHARSET_FARAWAY_BODY, and CHARSET_FARAWAY_HEADERS are triggered based on how this is set.
Examples:
ok_locales all (allow all locales)
ok_locales en (only allow English)
ok_locales en ja zh (allow English, Japanese, and Chinese)
Note: if there are multiple ok_locales lines, only the last one is used.
Select the locales to allow from the list below:
en - Western character sets in general
ja - Japanese character sets
ko - Korean character sets
ru - Cyrillic character sets
th - Thai character sets
zh - Chinese (both simplified and traditional) character sets
You could check for the locale and set this when configuring, I'm not sure it is worth it though, on my box, LANG is set to LANG=en_US.UTF-8 so I could take that and infer "en" from it.
Looking at my spam I don't seem to get a lot of non-english Spam, so I'm not sure this would help me.