--- tree.c.orig	Tue Mar 26 20:19:32 2002
+++ tree.c	Tue Mar 26 20:22:09 2002
@@ -2592,7 +2592,10 @@
 	return(old);
     }
     xmlUnlinkNode(cur);
-    cur->doc = old->doc;
+
+    if( cur->doc != old->doc )
+		xmlSetTreeDoc(cur, old->doc);
+
     cur->parent = old->parent;
     cur->next = old->next;
     if (cur->next != NULL)