New user registration - Fatal error: Call to undefined function iconv_mime_decode

Hello,

I installed a fresh version of Elgg 2.1 on my Mac with AMPP (http://ampps.com/download, Apache/PHP/MySql software) for my development / testing purposes.

All seems to work fine, but got some unexplanable (for me) error when I try to emulate user registration:

> Fatal error: Call to undefined function Zend\Mail\Header\iconv_mime_decode() in /Applications/AMPPS/path/to/my/installation/vendor/zendframework/zend-mail/src/Header/HeaderWrap.php on line 106

User is inserted in DB (as "to be confirmed"), but registration email is NOT sent; meanwhile, all files were copied on right locations (Zend included).

This error happens only when new users try to register on the site, i.e not if user is already existing.

There is something I'm missing, what could be cause of that? Thanks in advance.