diff --git a/src/main/java/org/bukkit/craftbukkit/command/VanillaCommandWrapper.java b/src/main/java/org/bukkit/craftbukkit/command/VanillaCommandWrapper.java
index e709825563..96a0ae1fe7 100644
--- a/src/main/java/org/bukkit/craftbukkit/command/VanillaCommandWrapper.java
+++ b/src/main/java/org/bukkit/craftbukkit/command/VanillaCommandWrapper.java
@@ -161,7 +161,7 @@ public final class VanillaCommandWrapper extends VanillaCommand {
         if (sender instanceof ProxiedCommandSender) {
             return ((ProxiedNativeCommandSender) sender).getHandle();
         }
-        return null;
+        throw new IllegalArgumentException("Cannot make " + sender + " a vanilla command listener");
     }
 
     private int getPlayerListSize(String as[]) {