[CentOS] apache mod_authnz_ldap: multiple servers syntaxes

Hello,
I'm trying this here first before moving to the apache list. Maybe
someone of you use mod_authnz_ldap with multiple ldap servers
declaration for redundancy.
With one server declared it is working.

Here is what I've tried for adding another one (space separated as read
in the apache's doc) :
....
AuthLDAPURL
ldaps://ldap1.example.com/ou=People,dc=example,dc=com?uid??(businessCategory=foo)
ldaps://ldap2.example.com/ou=People,dc=example,dc=com?uid??(businessCategory=foo)
....

Result:
Syntax error on line 43 of /etc/httpd/conf.d/trac.conf:
Invalid LDAP connection mode setting: must be one of NONE, SSL, or
TLS/STARTTLS


Second test with quotes (as seen with some googling):
....
AuthLDAPURL
"ldaps://ldap1.example.com/ou=People,dc=example,dc=com?uid??(businessCategory=foo)
ldaps://ldap2.example.com/ou=People,dc=example,dc=com?uid??(businessCategory=foo)"
....

Result:
Syntax error on line 43 of /etc/httpd/conf.d/trac.conf:
Bad URL encountered while parsing LDAP URL.

I've also tried to quote each ldap's declaration. No go.

Can someone show me the clean way to achieve this ?

Thanks,
kfx.