Comment 1 for bug 69226

Here is a patch that solves this (it works for 1.3.0). Requires iconv toolkit to be installed (http://ftp.gnu.org/pub/gnu/libiconv/libiconv-1.11.tar.gz). After installing iconv, applying patch and enabling iconv support in proftpd (use configure opions: --with-modules=mod_codeconv:mod_df) - simply add the following into your proftpd.conf:

<IfModule mod_codeconv.c>
CharsetLocal UTF-8
CharsetRemote CP1251
</IfModule>

Where CharsetLocal is a system charset on the server machine, and CharsetRemote - on the client one.

This patch solves problem not only with Cyrillic characters, but with any encoding supported by iconv (use iconv -l to view full list).

Have fun!