Description:
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Hi all,

I'm trying to install mailparse extension (https://pecl.php.net/package/mailparse) but it's fail, it tell me that mbstring extension is required, but it is (and enable)

I tried thought pecl and pickle, unfortunaly the result is same.

Test script:
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docker run --rm -it php:5.6-cli bash

docker-php-ext-configure mbstring

docker-php-ext-install mbstring

php -m | grep 'mbstring'
mbstring

php -r "print mb_convert_case('foo', MB_CASE_UPPER);"
FOO

pecl install mailparse


Expected result:
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Build process completed successfully
Installing '/usr/local/lib/php/extensions/no-debug-non-zts-20131226/mailparse.so'
install ok: channel://pecl.php.net/mailparse-2.1.6
configuration option "php_ini" is not set to php.ini location
You should add "extension=mailparse.so" to php.ini

Actual result:
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pecl/mailparse requires PHP extension "mbstring"
No valid packages found
install failed