Running openldap-2.4.31 on Ubuntu 14.04.1 LTS compiled with gnutls.

I created a local key and CSR using certtool:

server.csr

server.key

I was then issued the following from Network Solutions:

AddTrustExternalCARoot.crt

hostname.domain.com.crt

NetworkSolutions_CA.crt

UTNAddTrustServer_CA.crt

I added the following to slapd.conf:

TLSCertificateFile /etc/ldap/certs/hostname.domain.com.crt

TLSCertificateKeyFile /etc/ldap/certs/server.key

TLSCACertificateFile /etc/ldap/certs/NetworkSolutions_CA.crt

...and I now get the following error when I try to start slapd:

Oct 20 10:49:58 hostname slapd[3476]: main: TLS init def ctx failed: -1

Can someone point me in the right direction as to what I am missing here?