diff --git a/configure.ac b/configure.ac
index e592089ff..54e9aaa9f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-AC_INIT(nix, "0.9")
+AC_INIT(nix, "0.8")
 AC_CONFIG_SRCDIR(README)
 AC_CONFIG_AUX_DIR(config)
 AM_INIT_AUTOMAKE
diff --git a/scripts/download-using-manifests.pl.in b/scripts/download-using-manifests.pl.in
index 8c75ab109..ed3290c18 100644
--- a/scripts/download-using-manifests.pl.in
+++ b/scripts/download-using-manifests.pl.in
@@ -76,7 +76,7 @@ addToQueue $targetPath;
 
 sub isValidPath {
     my $p = shift;
-    system "@bindir@/nix-store --check-validity '$p' 2> /dev/null";
+    system "@bindir@/nix-store --isvalid '$p' 2> /dev/null";
     return $? == 0;
 }
 
diff --git a/scripts/generate-patches.pl.in b/scripts/generate-patches.pl.in
index b27181da4..3856dd568 100755
--- a/scripts/generate-patches.pl.in
+++ b/scripts/generate-patches.pl.in
@@ -237,10 +237,10 @@ foreach my $p (keys %dstOutPaths) {
             $ratio = 1 / $ratio if $ratio < 1;
             print "  USE $srcUses $dstUses $ratio $q\n";
             
-#            if ($ratio >= 2) {
-#                print "  SKIPPING $q due to use ratio $ratio ($srcUses $dstUses)\n";
-#                next;
-#            }
+            if ($ratio >= 2) {
+                print "  SKIPPING $q due to use ratio $ratio ($srcUses $dstUses)\n";
+                next;
+            }
 
             # If there are multiple matching names, include the ones
             # with the closest version numbers.
diff --git a/src/libstore/store.cc b/src/libstore/store.cc
index d61c3e454..4e531bc41 100644
--- a/src/libstore/store.cc
+++ b/src/libstore/store.cc
@@ -737,10 +737,10 @@ void deleteFromStore(const Path & _path)
     Transaction txn(nixDB);
     if (isValidPathTxn(txn, path)) {
         PathSet referers = getReferers(txn, path);
-        for (PathSet::iterator i = referers.begin();
-             i != referers.end(); ++i)
-            if (*i != path && isValidPathTxn(txn, *i))
-                throw Error(format("cannot delete path `%1%' because it is in use by path `%2%'") % path % *i);
+        if (referers.size() > 1 ||
+            (referers.size() == 1 &&
+                *referers.begin() != path))
+            throw Error(format("cannot delete path `%1%' because it is in use") % path);
         invalidatePath(txn, path);
     }
     txn.commit();