diff --git a/src/main/java/com/commafeed/backend/feeds/FeedRefreshUpdater.java b/src/main/java/com/commafeed/backend/feeds/FeedRefreshUpdater.java
new file mode 100644
index 00000000..93664737
--- /dev/null
+++ b/src/main/java/com/commafeed/backend/feeds/FeedRefreshUpdater.java
@@ -0,0 +1,33 @@
+package com.commafeed.backend.feeds;
+
+import java.util.Collection;
+
+import javax.ejb.Asynchronous;
+import javax.ejb.Stateless;
+import javax.inject.Inject;
+
+import org.apache.commons.collections.CollectionUtils;
+
+import com.commafeed.backend.dao.FeedDAO;
+import com.commafeed.backend.model.Feed;
+import com.commafeed.backend.model.FeedEntry;
+import com.commafeed.backend.services.FeedUpdateService;
+
+@Stateless
+public class FeedRefreshUpdater {
+
+	@Inject
+	FeedUpdateService feedUpdateService;
+
+	@Inject
+	FeedDAO feedDAO;
+
+	@Asynchronous
+	public void updateEntries(Feed feed, Collection<FeedEntry> entries) {
+		if (CollectionUtils.isNotEmpty(entries)) {
+			feedUpdateService.updateEntries(feed, entries);
+		}
+		feedDAO.update(feed);
+	}
+
+}
diff --git a/src/main/java/com/commafeed/backend/feeds/FeedRefreshWorker.java b/src/main/java/com/commafeed/backend/feeds/FeedRefreshWorker.java
index d6195c6e..29c05360 100644
--- a/src/main/java/com/commafeed/backend/feeds/FeedRefreshWorker.java
+++ b/src/main/java/com/commafeed/backend/feeds/FeedRefreshWorker.java
@@ -20,7 +20,6 @@ import org.slf4j.LoggerFactory;
 import com.commafeed.backend.HttpGetter.NotModifiedException;
 import com.commafeed.backend.model.Feed;
 import com.commafeed.backend.model.FeedEntry;
-import com.commafeed.backend.services.FeedUpdateService;
 import com.sun.syndication.io.FeedException;
 
 public class FeedRefreshWorker {
@@ -29,7 +28,7 @@ public class FeedRefreshWorker {
 			.getLogger(FeedRefreshWorker.class);
 
 	@Inject
-	FeedUpdateService feedUpdateService;
+	FeedRefreshUpdater feedRefreshUpdater;
 
 	@Inject
 	FeedFetcher fetcher;
@@ -127,7 +126,7 @@ public class FeedRefreshWorker {
 			feed.setEtagHeader(fetchedFeed.getFeed().getEtagHeader());
 			entries = fetchedFeed.getEntries();
 		}
-		feedUpdateService.updateEntries(feed, entries);
+		feedRefreshUpdater.updateEntries(feed, entries);
 
 	}
 
diff --git a/src/main/java/com/commafeed/backend/services/FeedUpdateService.java b/src/main/java/com/commafeed/backend/services/FeedUpdateService.java
index b3ac5da3..2d04b539 100644
--- a/src/main/java/com/commafeed/backend/services/FeedUpdateService.java
+++ b/src/main/java/com/commafeed/backend/services/FeedUpdateService.java
@@ -5,15 +5,14 @@ import java.util.Calendar;
 import java.util.Collection;
 import java.util.List;
 
-import javax.ejb.Asynchronous;
-import javax.ejb.Stateless;
+import javax.ejb.Lock;
+import javax.ejb.LockType;
+import javax.ejb.Singleton;
 import javax.inject.Inject;
 
-import org.apache.commons.collections.CollectionUtils;
 import org.apache.commons.lang.ObjectUtils;
 import org.apache.commons.lang.StringUtils;
 
-import com.commafeed.backend.dao.FeedDAO;
 import com.commafeed.backend.dao.FeedEntryDAO;
 import com.commafeed.backend.dao.FeedEntryStatusDAO;
 import com.commafeed.backend.dao.FeedSubscriptionDAO;
@@ -25,12 +24,9 @@ import com.commafeed.backend.model.FeedEntryStatus;
 import com.commafeed.backend.model.FeedSubscription;
 import com.google.common.collect.Lists;
 
-@Stateless
+@Singleton
 public class FeedUpdateService {
 
-	@Inject
-	FeedDAO feedDAO;
-
 	@Inject
 	FeedSubscriptionDAO feedSubscriptionDAO;
 
@@ -40,63 +36,58 @@ public class FeedUpdateService {
 	@Inject
 	FeedEntryStatusDAO feedEntryStatusDAO;
 
-	@Asynchronous
+	@Lock(LockType.WRITE)
 	public void updateEntries(Feed feed, Collection<FeedEntry> entries) {
 
-		if (CollectionUtils.isNotEmpty(entries)) {
-			List<FeedEntry> existingEntries = getExistingEntries(entries);
-			List<FeedSubscription> subscriptions = feedSubscriptionDAO
-					.findByFeed(feed);
+		List<FeedEntry> existingEntries = getExistingEntries(entries);
+		List<FeedSubscription> subscriptions = feedSubscriptionDAO
+				.findByFeed(feed);
 
-			List<FeedEntry> entryUpdateList = Lists.newArrayList();
-			List<FeedEntryStatus> statusUpdateList = Lists.newArrayList();
-			for (FeedEntry entry : entries) {
+		List<FeedEntry> entryUpdateList = Lists.newArrayList();
+		List<FeedEntryStatus> statusUpdateList = Lists.newArrayList();
+		for (FeedEntry entry : entries) {
 
-				FeedEntry foundEntry = findEntry(existingEntries, entry);
+			FeedEntry foundEntry = findEntry(existingEntries, entry);
 
-				if (foundEntry == null) {
-					FeedEntryContent content = entry.getContent();
+			if (foundEntry == null) {
+				FeedEntryContent content = entry.getContent();
 
-					content.setContent(FeedUtils.handleContent(content
-							.getContent()));
-					String title = FeedUtils.handleContent(content.getTitle());
-					if (title != null) {
-						content.setTitle(title.substring(0,
-								Math.min(2048, title.length())));
-					}
+				content.setContent(FeedUtils.handleContent(content.getContent()));
+				String title = FeedUtils.handleContent(content.getTitle());
+				if (title != null) {
+					content.setTitle(title.substring(0,
+							Math.min(2048, title.length())));
+				}
 
-					entry.setInserted(Calendar.getInstance().getTime());
-					entry.getFeeds().add(feed);
-					entryUpdateList.add(entry);
-				} else {
-					boolean foundFeed = false;
-					for (Feed existingFeed : foundEntry.getFeeds()) {
-						if (ObjectUtils.equals(existingFeed.getId(),
-								feed.getId())) {
-							foundFeed = true;
-							break;
-						}
-					}
-
-					if (!foundFeed) {
-						foundEntry.getFeeds().add(feed);
-						entryUpdateList.add(foundEntry);
+				entry.setInserted(Calendar.getInstance().getTime());
+				entry.getFeeds().add(feed);
+				entryUpdateList.add(entry);
+			} else {
+				boolean foundFeed = false;
+				for (Feed existingFeed : foundEntry.getFeeds()) {
+					if (ObjectUtils.equals(existingFeed.getId(), feed.getId())) {
+						foundFeed = true;
+						break;
 					}
 				}
-			}
-			for (FeedEntry entry : entryUpdateList) {
-				for (FeedSubscription sub : subscriptions) {
-					FeedEntryStatus status = new FeedEntryStatus();
-					status.setEntry(entry);
-					status.setSubscription(sub);
-					statusUpdateList.add(status);
+
+				if (!foundFeed) {
+					foundEntry.getFeeds().add(feed);
+					entryUpdateList.add(foundEntry);
 				}
 			}
-
-			feedEntryDAO.saveOrUpdate(entryUpdateList);
-			feedEntryStatusDAO.saveOrUpdate(statusUpdateList);
 		}
-		feedDAO.update(feed);
+		for (FeedEntry entry : entryUpdateList) {
+			for (FeedSubscription sub : subscriptions) {
+				FeedEntryStatus status = new FeedEntryStatus();
+				status.setEntry(entry);
+				status.setSubscription(sub);
+				statusUpdateList.add(status);
+			}
+		}
+
+		feedEntryDAO.saveOrUpdate(entryUpdateList);
+		feedEntryStatusDAO.saveOrUpdate(statusUpdateList);
 	}
 
 	private FeedEntry findEntry(List<FeedEntry> existingEntries, FeedEntry entry) {