Comment 1 for bug 222038

The problem is in the (generated) file /etc/firestarter/firestarter.sh. The following lines:

IP=`/sbin/ifconfig $IF | grep inet | cut -d : -f 2 | cut -d \\ -f 1`
MASK=`/sbin/ifconfig $IF | grep Mas | cut -d : -f 4`
BCAST=`/sbin/ifconfig $IF |grep Bcast: | cut -d : -f 3 | cut -d \\ -f 1`

fails when the local is other than English, because they look up several keyword ("Mas", "Bcast:") which doesn't appears in ifconfig in Spanish. Example:

ricardo@kadath:~$ LANG=C ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:18:f3:53:b2:9a
          inet addr:192.168.2.100 Bcast:192.168.2.255 Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
          RX packets:2736 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2634 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:2917432 (2.7 MB) TX bytes:368744 (360.1 KB)
          Interrupt:18 Base address:0xa000

ricardo@kadath:~$ ifconfig eth0
eth0 Link encap:Ethernet direcciónHW 00:18:f3:53:b2:9a
          inet dirección:192.168.2.100 Difusión:192.168.2.255 Máscara:255.255.255.0
          ARRIBA DIFUSIÓN CORRIENDO MULTICAST MTU:1500 Metric:1
          RX packets:2723 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2620 errors:0 dropped:0 overruns:0 carrier:0
          colisiones:0 txqueuelen:1000
          RX bytes:2908959 (2.7 MB) TX bytes:365950 (357.3 KB)
          Interrupción:18 Dirección base: 0xa000

As a workaround, you can hack the /etc/firestarter/firestarter.sh file, replacing the three above lines with the following:

IP=`LANG=C /sbin/ifconfig $IF | grep inet | cut -d : -f 2 | cut -d \\ -f 1`
MASK=`LANG=C /sbin/ifconfig $IF | grep Mas | cut -d : -f 4`
BCAST=`LANG=C /sbin/ifconfig $IF |grep Bcast: | cut -d : -f 3 | cut -d \\ -f 1`