compile:
[javac] Compiling 931 source files to /home/l2dev/updates/nextupdate/gs1900/L2J-C4-SL/build/classes
[javac] /home/l2dev/updates/nextupdate/gs1900/L2J-C4-SL/java/net/sf/l2j/gameserver/PacketHandler.java:38: cannot find symbol
[javac] symbol : class CustomPacketHandlerInterface
[javac] location: class net.sf.l2j.gameserver.PacketHandler
[javac] private static LinkedList<CustomPacketHandlerInterface> customhandlers = new LinkedList<CustomPacketHandlerInterface>();
[javac] ^
[javac] /home/l2dev/updates/nextupdate/gs1900/L2J-C4-SL/java/net/sf/l2j/gameserver/PacketHandler.java:44: cannot find symbol
[javac] symbol : class CustomPacketHandlerInterface
[javac] location: class net.sf.l2j.gameserver.PacketHandler
[javac] public static void addCustomHandler(CustomPacketHandlerInterface handler) {
[javac] ^
[javac] /home/l2dev/updates/nextupdate/gs1900/L2J-C4-SL/java/net/sf/l2j/gameserver/PacketHandler.java:48: cannot find symbol
[javac] symbol : class CustomPacketHandlerInterface
[javac] location: class net.sf.l2j.gameserver.PacketHandler
[javac] public static void removeCustomHandler(CustomPacketHandlerInterface handler) {
[javac] ^
[javac] /home/l2dev/updates/nextupdate/gs1900/L2J-C4-SL/java/net/sf/l2j/gameserver/PacketHandler.java:38: cannot find symbol
[javac] symbol : class CustomPacketHandlerInterface
[javac] location: class net.sf.l2j.gameserver.PacketHandler
[javac] private static LinkedList<CustomPacketHandlerInterface> customhandlers = new LinkedList<CustomPacketHandlerInterface>();
[javac] ^
[javac] /home/l2dev/updates/nextupdate/gs1900/L2J-C4-SL/java/net/sf/l2j/gameserver/PacketHandler.java:57: cannot find symbol
[javac] symbol : class CustomPacketHandlerInterface
[javac] location: class net.sf.l2j.gameserver.PacketHandler
[javac] for (CustomPacketHandlerInterface handler : customhandlers) {
[javac] ^
[javac] Note: Some input files use or override a deprecated API.
[javac] Note: Recompile with -Xlint:deprecation for details.
[javac] Note: Some input files use unchecked or unsafe operations.
[javac] Note: Recompile with -Xlint:unchecked for details.
[javac] 5 errors