Re: How I can make BGP configuration on SSG-140

Example for the one peer.  Assign the 145.148.140.121 address to ethernet 0/2

Add the BGP to the VR and set the neighbors

set vr untrust protocol bgp 57344
set vr untrust-vr protocol bgp enable 
set vrouter "untrust-vr" protocol bgp neighbor 145.148.140.126 remote-as 4578 local-ip 145.148.140.121/32 outgoing-interface ethernet0/2
set vr untrust-vr protocol bgp neighbor 145.148.140.126 enable
set interface e0/2 protocol bgp

Export policy added to for route advertisment as desired.  This assumes you create a static route for this subnet and forward this on your device.  If this is a direct route

set vrouter "untrust-vr"
set access-list 1
set access-list 1 permit ip 72.142.56.0/24 1
set route-map name "route-map" permit 1
set match ip 1
exit
static route:
set route 72.142.56.0/24 interface ethernet0/x gateway x.x.x.x
set vrouter trust-vr protocol bgp redistribute route-map route-map protocol static

direct route:
set vrouter trust-vr protocol bgp redistribute route-map route-map protocol direct

Documentation

Chapter 35 on BGP

http://www.juniper.net/techpubs/software/screenos/screenos6.3.0/630_ce_all.pdf