diff --git a/README b/README
index 19883281..53f2e0c5 100644
--- a/README
+++ b/README
@@ -2,6 +2,14 @@ To get started, ensure you have the latest JDK installed, and download Maven fro
 
   http://maven.apache.org/
 
+and install the protobuf compiler package version 2.4.x:
+
+  Debian/Ubuntu: apt-get install protobuf-compiler
+
+  Windows: http://code.google.com/p/protobuf/downloads/list
+
+  OSX: install from ports?
+
 Then run "mvn clean package" to compile the software. You can also run "mvn site:site" to generate a website with
 useful information like JavaDocs. The outputs are under the target/ directory.
 
diff --git a/pom.xml b/pom.xml
index 65252472..78a7f0a7 100644
--- a/pom.xml
+++ b/pom.xml
@@ -324,7 +324,7 @@
     <junit.version>4.8.2</junit.version>
     <slf4j.version>1.6.2</slf4j.version>
     <derby.version>10.8.2.2</derby.version>
-    <protobuf.version>2.2.0</protobuf.version>
+    <protobuf.version>2.4.1</protobuf.version>
     <generated.sourceDirectory>gen</generated.sourceDirectory>
   </properties>
 
diff --git a/src/com/google/bitcoin/core/Wallet.java b/src/com/google/bitcoin/core/Wallet.java
index 3fd988da..dcc75373 100644
--- a/src/com/google/bitcoin/core/Wallet.java
+++ b/src/com/google/bitcoin/core/Wallet.java
@@ -200,7 +200,7 @@ public class Wallet implements Serializable {
         // Pending and inactive can overlap, so merge them before counting
         HashSet<Transaction> pendingInactive = new HashSet<Transaction>();
         pendingInactive.addAll(pending.values());
-        pendingInactive.retainAll(inactive.values());
+        pendingInactive.addAll(inactive.values());
         
         return getTransactions(true, true).size() ==
                unspent.size() + spent.size() + pendingInactive.size() + dead.size();