Yes, i think it is a route problem but i don't know what i did wrong,
here are the route table:
The gateway - vpn server:
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.100.1 0.0.0.0 255.255.255.255 UH 0 0 0 ppp0
10.254.100.2 0.0.0.0 255.255.255.255 UH 0 0 0 tun0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
0.0.0.0 192.168.100.1 0.0.0.0 UG 0 0 0 ppp0
One of the clients in the lan (192.168.1.2):
===========================================================================
Route attive:
Indirizzo rete Mask Gateway Interfac. Metric
0.0.0.0 0.0.0.0 192.168.1.1 192.168.1.2 1
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
192.168.1.0 255.255.255.0 192.168.1.2 192.168.1.2 1
192.168.1.2 255.255.255.255 127.0.0.1 127.0.0.1 1
192.168.1.255 255.255.255.255 192.168.1.2 192.168.1.2 1
224.0.0.0 224.0.0.0 192.168.1.2 192.168.1.2 1
255.255.255.255 255.255.255.255 192.168.1.2 192.168.1.2 1
Gateway predefinito: 192.168.1.1
===========================================================================
Route persistenti:
Nessuno