Disabling the LDAP cache solves the bus error problem
on Solaris but probably causes a performance problem
for high traffic sites:

<IfModule util_ldap.c>
    LDAPCacheEntries 0
    LDAPOpCacheEntries 0
</IfModule>


<Directory /my-directory>
    ... other directives ...

    <IfModule util_ldap.c>
        <IfModule mod_auth.c>
            <IfModule mod_auth_ldap.c>
                AuthLDAPEnabled on
                AuthLDAPAuthoritative on
                AuthLDAPURL "ldap://my-ldap-host:389/ou=People, dc=my-domain, dc=my-tld?uid?sub?(objectClass=*)"
            </IfModule>
            AuthType basic
            AuthName local
            require valid-user
        </IfModule>
    </IfModule>

    ... other directives ...
</Directory>