Wilfried,
Your ge-0/0/0 interface is expecting tagged packets with vlan-id 7. For the SRX, in between, to keep those tags it has to have its interfaces in trunk mode:
vlan7 {
vlan-id 7;
}
and ge-0/0/5 and ge-0/0/6 as:
ge-0/0/X {
unit 0 {
family ethernet-switching {
port-mode trunk;
vlan {
members [ vlan4 ];
}
}
Try it and let us know. If it works please mark it as Resolved =P