--- /dev/null
+diff --git a/mailnews/imap/src/nsImapFlagAndUidState.cpp b/mailnews/imap/src/nsImapFlagAndUidState.cpp
+--- a/mailnews/imap/src/nsImapFlagAndUidState.cpp
++++ b/mailnews/imap/src/nsImapFlagAndUidState.cpp
+@@ -171,17 +171,17 @@ NS_IMETHODIMP nsImapFlagAndUidState::Res
+ {
+ PR_CEnterMonitor(this);
+ if (!howManyLeft)
+ fNumberOfMessagesAdded = fNumberDeleted = 0; // used space is still here
+ if (m_customFlagsHash.IsInitialized())
+ m_customFlagsHash.EnumerateRead(FreeCustomFlags, nsnull);
+ memset(fFlags, 0, sizeof(imapMessageFlagsType) * fNumberOfMessageSlotsAllocated);
+ m_customFlagsHash.Clear();
+- memset(fUids.Elements(), fNumberOfMessageSlotsAllocated * sizeof(nsMsgKey), 0);
++ memset(fUids.Elements(), 0, fNumberOfMessageSlotsAllocated * sizeof(nsMsgKey));
+ fPartialUIDFetch = PR_TRUE;
+ PR_CExitMonitor(this);
+ return NS_OK;
+ }
+
+
+ // Remove (expunge) a message from our array, since now it is gone for good