>>133
map sppp0 192.168.10.0/24 -> xxx.xxx.xxx.xxx/32 proxy port ftp ftp/tcp mssclamp 1414
map sppp0 192.168.10.0/24 -> xxx.xxx.xxx.xxx/32 portmap tcp/udp 10000:65000 mssclamp 1414
map sppp0 192.168.10.0/24 -> xxx.xxx.xxx.xxx/32 mssclamp 1414

でどうよ?