diff --git a/pom.xml b/pom.xml
index eb98213b..0dcbd9fc 100644
--- a/pom.xml
+++ b/pom.xml
@@ -67,7 +67,7 @@
     <dependency>
       <groupId>com.google.guava</groupId>
       <artifactId>guava</artifactId>
-      <version>r07</version>
+      <version>r08</version>
       <scope>compile</scope>
     </dependency>
     <dependency>
diff --git a/src/main/java/com/threerings/media/util/AStarPathUtil.java b/src/main/java/com/threerings/media/util/AStarPathUtil.java
index faf18030..f166f4e9 100644
--- a/src/main/java/com/threerings/media/util/AStarPathUtil.java
+++ b/src/main/java/com/threerings/media/util/AStarPathUtil.java
@@ -23,12 +23,14 @@ package com.threerings.media.util;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Set;
 import java.util.SortedSet;
 import java.util.TreeSet;
 
 import java.awt.Point;
 
 import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
 
 import com.samskivert.util.HashIntMap;
 
@@ -324,7 +326,7 @@ public class AStarPathUtil
         public SortedSet<Node> open;
 
         /** The set of closed nodes being searched. */
-        public ArrayList<Node> closed;
+        public Set<Node> closed;
 
         /** The destination coordinates in the tile array. */
         public int destx, desty;
@@ -344,7 +346,7 @@ public class AStarPathUtil
 
             // construct the open and closed lists
             open = new TreeSet<Node>();
-            closed = Lists.newArrayList();
+            closed = Sets.newIdentityHashSet();
         }
 
         /**