Linphone for Linux root_ca path defined as /etc/ssl/certs and linphone doesn't see rootca.pem flile in /usr/local/share/linphone/rootca.pem I think this is the bug in ./coreapi/linphonecore.c.
Also something wrong with ORTP + TLS -> broken pipe. I've checked my TLS connection by the Blink sip program ( http://icanblink.com ) - it works fine with the same certificates.