You can either use 0.0.0.0 as IP andress and Mask to allow everyone, but this will open the server-manager.
If you only want to open /user-manager, you should create a custom template for /etc/e-smith/templates/etc/httpd/conf/httpd.conf/VirtualHosts/27ManagerProxyPass and edit the first part like this:
foreach $place ('server-common','user-password')
{
if (($port eq "80") && ($haveSSL eq 'yes') && ($plainTextAccess ne 'yes'))
{
$OUT .= " RewriteRule ^/$place(/.*|\$) https://%{HTTP_HOST}/$place\$1 [L,R]\n";
} else {
$OUT .= " ProxyPass /$place http://127.0.0.1:${'httpd-admin'}{TCPPort}/$place\n";
$OUT .= " ProxyPassReverse /$place http://127.0.0.1:${'httpd-admin'}{TCPPort}/$place\n";
}
$OUT .= " <Location /$place>\n";
$OUT .= " order deny,allow\n";
$OUT .= " deny from all\n";
$OUT .= " allow from all\n";
$OUT .= " </Location>\n";
}