I think issue 0006474 is involved here.

Same symptom for 'euc-kr'.
Issue 0006474 is set to resolved in 1.1.0 string api, but i'm not sure it's done.

• ISO-8859-1, ISO-8859-15, UTF-8, cp1252, BIG5, GB2312, BIG5-HKSCS, SJIS, EUC-JP ( > PHP4.1.0)
• cp866, cp1251, KOI8-R ( > PHP 4.3.2)

DB's also encoded euc-kr.

afterall, temporarilly disabled inline waring for my case;

$g_display_errors = array(
    E_WARNING => 'none',
    E_NOTICE => 'none',
    E_USER_ERROR => 'halt',
    E_USER_WARNING => 'none',
    E_USER_NOTICE => 'none'
);

See my 0007235 for the solution.

There is a simple and good solution: Use UTF8.
See 0007049:0012854 in issue 0007049 and 0007235:0013111 in issue 0007235.

I wonder if "use UTF-8" is a solution for a problem where a simply WRONG ISO charset has been entered in source files.

I can confirm that this issue exists at my bugtracker (http://bugtracker.driverpacks.net/) too. I checked bug 0007235 to find the solution, but it was closed to continue the discussion here.

Could somebody confirm that the solution suggested in 0007235 IS indeed the solution? If not, could somebody please point me to a solution?

@wimleers: As the non-existing iso definition was placed in the Mantis sources, I ran into problems with our Czech forums - like many other Mantis users did. My solution as listed in 0007235 works fine and is safe for older browsers which do not support 'utf-8' already. But if you can be sure that your visitors do only use utf-8 compatible browsers, you can use 'utf-8', of course.

It's your choice.

The same bug happens for iso-8859-9 -- actually for any charset that is not supported by the htmlspecial* functions.

A second charset definition for these functions in the language filesshould do the trick?

I wonder WHO entered these undefined iso definitions into the source code. Shouldn't he/she simply correct these mistakes instead of forcing us to fix the sources or create hacks?

@UlfDunkel: thanks for confirming that that IS a solution. I made the changes you suggested to both the Polish and the Czech language files and can confirm that it's working flawlessly now! :) Thanks!

Fixed for all languages involved.