Made mod_MinecraftForge extend NetworkMod, and changed NetworkMod to extend BaseModMP server side.

forge/forge_client/src/net/minecraft/src/mod_MinecraftForge.java

@@ -2,11 +2,12 @@ package net.minecraft.src;
 
 import net.minecraft.src.forge.ForgeHooks;
 import net.minecraft.src.forge.MinecraftForge;
+import net.minecraft.src.forge.NetworkMod;
 
 /**
  * This class is just here to make the Forge version show up nicely in the ModLoader logs/Crash Screen
  */
-public class mod_MinecraftForge extends BaseMod
+public class mod_MinecraftForge extends NetworkMod
 {
     @Override
     public String getVersion()
@@ -21,4 +22,16 @@ public class mod_MinecraftForge extends BaseMod
     {
         MinecraftForge.getDungeonLootTries(); //Random thing to make things Initialize
     }
+
+	@Override
+	public boolean clientSideRequired() 
+	{
+		return false;
+	}
+
+	@Override
+	public boolean serverSideRequired() 
+	{
+		return false;
+	}
 }

forge/forge_server/src/net/minecraft/src/forge/NetworkMod.java

@@ -0,0 +1,25 @@
+package net.minecraft.src.forge;
+
+import net.minecraft.src.BaseModMp;
+
+/**
+ * This is for mods that are designed to be used on the server side alone,
+ * or both the client and server side. This class is used when registering
+ * various things relating to network traffic. Entity ID's, GUI Id's, etc..
+ */
+public abstract class NetworkMod extends BaseModMp
+{
+    /**
+     * Returns true if every client is required to have this
+     * mod installed when it is installed on a server.
+     * @return True if client is required, false if not.
+     */
+    public abstract boolean clientSideRequired();
+
+    /**
+     * Returns true if the server is required to have this
+     * mod when it is installed on the client.
+     * @return True if server is required, false if not.
+     */
+    public abstract boolean serverSideRequired();
+}

forge/forge_server/src/net/minecraft/src/mod_MinecraftForge.java

@@ -2,11 +2,12 @@ package net.minecraft.src;
 
 import net.minecraft.src.forge.ForgeHooks;
 import net.minecraft.src.forge.MinecraftForge;
+import net.minecraft.src.forge.NetworkMod;
 
 /**
  * This class is just here to make the Forge version show up nicely in the ModLoader logs/Crash Screen
  */
-public class mod_MinecraftForge extends BaseModMp
+public class mod_MinecraftForge extends NetworkMod
 {
     @Override
     public String getVersion()
@@ -21,4 +22,16 @@ public class mod_MinecraftForge extends BaseModMp
     {
         MinecraftForge.getDungeonLootTries(); //Random thing to make things Initialize
     }
+
+	@Override
+	public boolean clientSideRequired() 
+	{
+		return false;
+	}
+
+	@Override
+	public boolean serverSideRequired() 
+	{
+		return false;
+	}
 }