diff --git a/Foundation/CPArray/CPMutableArray.j b/Foundation/CPArray/CPMutableArray.j
index a1b3538ee..b82eb07ed 100644
--- a/Foundation/CPArray/CPMutableArray.j
+++ b/Foundation/CPArray/CPMutableArray.j
@@ -218,7 +218,7 @@
 */
 - (void)removeObject:(id)anObject
 {
-    [self removeObject:anObject inRange:CPMakeRange(0, self.length)];
+    [self removeObject:anObject inRange:CPMakeRange(0, [self count])];
 }
 
 /*!
@@ -233,7 +233,7 @@
     while ((index = [self indexOfObject:anObject inRange:aRange]) != CPNotFound)
     {
         [self removeObjectAtIndex:index];
-        aRange = CPIntersectionRange(CPMakeRange(index, self.length - index), aRange);
+        aRange = CPIntersectionRange(CPMakeRange(index, [self count] - index), aRange);
     }
 }
 
diff --git a/Tests/Foundation/CPMutableArrayTest.j b/Tests/Foundation/CPMutableArrayTest.j
index 1633f9fc1..3164350cc 100644
--- a/Tests/Foundation/CPMutableArrayTest.j
+++ b/Tests/Foundation/CPMutableArrayTest.j
@@ -92,6 +92,17 @@
     }];
 }
 
+- (void)test_removeObject_
+{
+    var arrayClass = [[self class] arrayClass],
+        a = [CPDate distantFuture],
+        b = [a copy],
+        c = [CPDate distantPast],
+        array = [arrayClass arrayWithObjects:a, b, a, c, b];
+
+    [array removeObject:a];
+    [self assert:array equals:[arrayClass arrayWithObjects:c]];
+}
 - (void)test_removeObjectsAtIndexes_
 {
     var arrayClass = [[self class] arrayClass],