When the command "/etc/rc.d/inet.d/network start" is issued. IP aliases as defined in ifcfg-eth0:0, ifcfg-eth0:1 etc. isn't started, when linuxconf for security reasons have been removed. This is properly due to a bug in the ifup-aliases script ?
ip aliases created with linuxconf require linuxconf to run. To flag it as an alias not created by linuxconf, add "DEVICE=eth0:0" (or whatever) to the alias definition.
Linuxconf, was removed before the IP alias files was created. All virtual hosts files ifcfg-eth0:0 et was written by hand ! Anyway, the trick with a DEVICE=eth0:0 solves the problem. Thanks !