Index: src/main/java/org/apache/james/mailbox/store/mail/AbstractMessageMapper.java
===================================================================
--- src/main/java/org/apache/james/mailbox/store/mail/AbstractMessageMapper.java	(revision 1504935)
+++ src/main/java/org/apache/james/mailbox/store/mail/AbstractMessageMapper.java	(working copy)
@@ -77,7 +77,7 @@
         Iterator<Message<Id>> messages = findInMailbox(mailbox, set, FetchType.Metadata, -1);
         
         long modSeq = -1;
-        if (messages.hasNext() == false) {
+        if (messages.hasNext()) {
             // if a mailbox does not support mod-sequences the provider may be null
             if (modSeqProvider != null) {
                 modSeq = modSeqProvider.nextModSeq(mailboxSession, mailbox);