Enabling StartTLS fails due to self-signed certificate in certificate chain

• After enabling StartTLS and installing a certificate:

Error:

Validate the Ldap configuration procedure failed
[ 0 ms] Hostname found in Name Service Cache
[ 1] Hostname found in Name Service Cache
[ 1] IP Address found in Name Service Cache
[ 1] Resolved LDAP servers: 192.168.207.29, 192.168.207.28.
Vserver: 29
[ 12] Successfully connected to ip 192.168.207.28, port 389
using TCP
[ 21] Unable to start TLS: Connect error
[ 21] Additional info: error:0A000086:SSL routines::certificate
verify failed (self-signed certificate in certificate
chain)
[ 21] Unable to connect to LDAP (NIS & Name Mapping) service on
ipao.be
[ 23] Successfully connected to ip 192.168.207.21, port 389
using TCP
[ 30] Unable to start TLS: Connect error
[ 30] Additional info: error:0A000086:SSL routines::certificate
verify failed (self-signed certificate in certificate
chain)
[ 30] Unable to connect to LDAP (NIS & Name Mapping) service on
ldap.somewhere.net
[ 30] No servers available for LDAP_NIS_AND_NAME_MAPPING,
vserv

• EMS and SECD:

[    62] Unable to start TLS: Connect error 
[    62] Additional info: error:0A000086:SSL routines::certificate verify failed (self-signed certificate in certificate chain)