chinese characters in excel and word become unrecognized

[redhatlinux10]

I installed instantmantis 1.0.8 a few days ago.and it now can input and display chinese characters properly in webpages.
the steps what i take are followed:
change mysql's character set to utf8 by adding some code in my.ini

Code: Select all

character-set-server = utf8
collation-server = utf8_general_ci

edit core.php

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header( 'Content-type: text/html;charset=' . lang_get( 'charset' ) );

to

Code: Select all

header( 'Content-type: text/html;charset=utf-8');

but now i found chinese characters in excel and word become unrecognized ,can somebody help me out?
thanks a lot in advance.