diff -r e9f7ba4718e1 -r a59acc683080 Source/BitHolder.m
--- a/Source/BitHolder.m	Fri Mar 07 11:43:02 2008 -0800
+++ b/Source/BitHolder.m	Thu May 29 15:04:06 2008 -0700
@@ -46,8 +46,12 @@
 - (void) setBit: (Bit*)bit
 {
     if( bit != self.bit ) {
-        if( bit && _bit )
-            [_bit destroy];
+        if( _bit ) {
+            if( bit )
+                [_bit destroy];
+            else
+                [_bit removeFromSuperlayer];
+        }
         setObj(&_bit,bit);
         ChangeSuperlayer(bit,self,-1);
     }