FreeTDS missing encryption support to connect to MS SQL

I'm running a Gentoo Linux and I'm trying to connect to MS SQL via pyodbc using freetds. I enabled the debug log in freetds. Now when I try to connect I'm seeing this: 18:13:00.841828 13523 (net.c:270):tds_open_socket: connect(2) returned "Operation now in progress" 18:13:00.955976 13523 (net.c:310):tds_open_socket() succeeded 18:13:00.955996 13523 (util.c:156):Changed query state from DEAD to IDLE 18:13:00.956017 13523 (net.c:741):Sending packet 0000 12 01 00 34 00 00 00 00-00 00 15 00 06 01 00 1b |...4.... ........| 0010 00 01 02 00 1c 00 0c 03-00 28 00 04 ff 08 00 01 |........ .(......| 0020 55 00 00 02 4d 53 53 51-4c 53 65 72 76 65 72 00 |U...MSSQ LServer.| 0030 d3 34 00 00 - |.4..| 18:13:01.190745 13523 (net.c:555):Received header 0000 04 01 00 25 00 00 01 00- |...%....| 18:13:01.190772 13523 (net.c:609):Received packet 0000 04 01 00 25 00 00 01 00-00 00 15 00 06 01 00 1b |...%.... ........| 0010 00 01 02 00 1c 00 01 03-00 1d 00 00 ff 0a 32 10 |........ ......2.| 18:13:01.190781 13523 (login.c:1057):detected flag 3 18:13:01.190783 13523 (login.c:1068):server required encryption but support is not compiled in 18:13:01.190785 13523 (login.c:466):login packet rejected 18:13:01.190821 13523 (util.c:156):Changed query state from IDLE to DEAD This sounds like the support for some encryption is missing, but I don't know which one. My freetds is complied with these configure parameters: ./configure --prefix=/usr --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --mandir=/usr/share/man --infodir=/usr/share/info --datadir=/usr/share --sysconfdir=/etc --localstatedir=/var/lib --disable-dependency-tracking --libdir=/usr/lib64 --with-tdsver=7.0 --enable-msdblib --enable-odbc --with-unixodbc=/usr --enable-krb5 As far as I know it's using libkrb5 for the encryption. These are the configure flags for my libkrb5: ./configure --prefix=/usr --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --mandir=/usr/share/man --infodir=/usr/share/info --datadir=/usr/share --sysconfdir=/etc --localstatedir=/var/lib --libdir=/usr/lib64 --without-ldap --without-tcl --enable-pkinit --enable-thread-support --without-hesiod --enable-shared --with-system-et --with-system-ss --enable-dns-for-realm --enable-kdc-lookaside-cache --with-system-verto --disable-rpath --with-pkinit-crypto-impl=openssl Does somebody know which configure flags I'm missing to be able to connect to MS SQL?