diff --git a/src/com/fsck/k9/helper/HtmlConverter.java b/src/com/fsck/k9/helper/HtmlConverter.java
index fefa22d2c..80da74c04 100644
--- a/src/com/fsck/k9/helper/HtmlConverter.java
+++ b/src/com/fsck/k9/helper/HtmlConverter.java
@@ -52,14 +52,15 @@ public class HtmlConverter {
      */
     private static class HtmlToTextTagHandler implements Html.TagHandler {
         // List of tags whose content should be ignored.
-        private static final Set<String> TAGS_WITH_IGNORED_CONTENT = Collections.unmodifiableSet(new HashSet<String>() {
-            {
-                add("style");
-                add("script");
-                add("title");
-                add("!");   // comments
-            }
-        });
+        private static final Set<String> TAGS_WITH_IGNORED_CONTENT;
+        static {
+            Set<String> set = new HashSet<String>();
+            set.add("style");
+            set.add("script");
+            set.add("title");
+            set.add("!");   // comments
+            TAGS_WITH_IGNORED_CONTENT = Collections.unmodifiableSet(set);
+        }
 
         @Override
         public void handleTag(boolean opening, String tag, Editable output, XMLReader xmlReader) {
diff --git a/src/com/fsck/k9/mail/store/LocalStore.java b/src/com/fsck/k9/mail/store/LocalStore.java
index ffb2f8abf..38300b2ff 100644
--- a/src/com/fsck/k9/mail/store/LocalStore.java
+++ b/src/com/fsck/k9/mail/store/LocalStore.java
@@ -5,6 +5,7 @@ import java.io.*;
 import java.net.URLEncoder;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -78,18 +79,21 @@ public class LocalStore extends Store implements Serializable {
 
     private static final Flag[] PERMANENT_FLAGS = { Flag.DELETED, Flag.X_DESTROYED, Flag.SEEN, Flag.FLAGGED };
 
-    private static Set<String> HEADERS_TO_SAVE = new HashSet<String>();
+    private static final Set<String> HEADERS_TO_SAVE;
     static {
-        HEADERS_TO_SAVE.add(K9.IDENTITY_HEADER);
-        HEADERS_TO_SAVE.add("To");
-        HEADERS_TO_SAVE.add("Cc");
-        HEADERS_TO_SAVE.add("From");
-        HEADERS_TO_SAVE.add("In-Reply-To");
-        HEADERS_TO_SAVE.add("References");
-        HEADERS_TO_SAVE.add("Content-ID");
-        HEADERS_TO_SAVE.add("Content-Disposition");
-        HEADERS_TO_SAVE.add("User-Agent");
+        Set<String> set = new HashSet();
+        set.add(K9.IDENTITY_HEADER);
+        set.add("To");
+        set.add("Cc");
+        set.add("From");
+        set.add("In-Reply-To");
+        set.add("References");
+        set.add("Content-ID");
+        set.add("Content-Disposition");
+        set.add("User-Agent");
+        HEADERS_TO_SAVE = Collections.unmodifiableSet(set);
     }
+
     /*
      * a String containing the columns getMessages expects to work with
      * in the correct order.