Description of problem:

system-config-network saves gateway value instead of netmask value in NETMASK=
/etc/sysconfig/network-scripts/ifcfg-ethX
when using static IP.

Version-Release number of selected component (if applicable):
system-config-network-tui-1.5.93-2.fc10.noarch

How reproducible:

run system-config-network and set static IP address for eth0, for example:

IP: 10.0.0.2
NETMASK: 255.255.255.0
GATEWAY: 10.0.0.1

then the tool will write in /etc/sysconfig/network-scripts/ifcfg-eth0:

NETMASK=10.0.0.1  <----
IPADDR=10.0.0.2
NM_CONTROLLED=no
GATEWAY=10.0.0.1
TYPE=Ethernet

which should be:
NETMASK=255.255.255.0

Result: no default route set --> no network