diff --git a/NUIParse/Parsers/NUIPShiftReduceParsers/NUIPItem.h b/NUIParse/Parsers/NUIPShiftReduceParsers/NUIPItem.h
index 7d32c34..c68655c 100644
--- a/NUIParse/Parsers/NUIPShiftReduceParsers/NUIPItem.h
+++ b/NUIParse/Parsers/NUIPShiftReduceParsers/NUIPItem.h
@@ -28,9 +28,3 @@
 - (BOOL)isEqualToItem:(NUIPItem *)item;
 
 @end
-
-@interface NSObject (NUIPIsItem)
-
-- (BOOL)isItem;
-
-@end
diff --git a/NUIParse/Parsers/NUIPShiftReduceParsers/NUIPItem.m b/NUIParse/Parsers/NUIPShiftReduceParsers/NUIPItem.m
index 1957cc8..77b0385 100644
--- a/NUIParse/Parsers/NUIPShiftReduceParsers/NUIPItem.m
+++ b/NUIParse/Parsers/NUIPShiftReduceParsers/NUIPItem.m
@@ -76,14 +76,9 @@ - (id)itemByMovingDotRight
     return [c autorelease];
 }
 
-- (BOOL)isItem
-{
-    return YES;
-}
-
 - (BOOL)isEqual:(id)object
 {
-    return [object isItem] && ((NUIPItem *)object)->position == position && ((NUIPItem *)object)->rule == rule;
+    return [object isKindOfClass:[NUIPItem class]] && [self isEqualToItem:object];
 }
 
 - (BOOL)isEqualToItem:(NUIPItem *)item
@@ -118,12 +113,3 @@ - (NSString *)description
 }
 
 @end
-
-@implementation NSObject (NUIPIsItem)
-
-- (BOOL)isItem
-{
-    return NO;
-}
-
-@end