Code:
#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#
# Interfaction Options
#
# InterfactionChat
# This directive controls whether horde and alliance players can talk to each other.
# Default: 0 (disabled)
#
# InterfactionGroup
# This directive controls whether horde and alliance players are able to build a group together.
# Default: 0 (disabled)
#
# InterfactionGuild
# This directive controls whether horde and alliance players are able to build crossfaction guilds
# Default: 0 (disabled)
#
# InterfactionTrade
# This directive controls whether horde and alliance players can trade with each other.
# Default: 0 (disabled)
#
# InterfactionFriends
# If this is enabled players can add other players from the opposite faction to their friends list
# Default: 0 (disabled)
#
# InterfactionMisc
# This directive controls whether horde and alliance players are able to use different functions
# on players of the opposite faction. This includes e.g. using the /who command.
# Default: 0 (disabled)
#
# CrossOverCharacters
# If this is enabled players are able to create both, horde and alliance characters on a PVP realm.
# Default: 0 (disabled)
#
#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#
<Interfaction InterfactionChat="0"
InterfactionGroup="0"
InterfactionGuild="0"
InterfactionTrade="0"
InterfactionFriends="0"
InterfactionMisc="0"
CrossOverCharacters="0">
This is from the Arcemu-optional.config file, you can read what everything is doing.