diff --git a/mailnews/imap/public/nsIImapMailFolderSink.idl b/mailnews/imap/public/nsIImapMailFolderSink.idl
index b0c35e73a84d..a5de8d5fc249 100644
--- a/mailnews/imap/public/nsIImapMailFolderSink.idl
+++ b/mailnews/imap/public/nsIImapMailFolderSink.idl
@@ -69,7 +69,6 @@ interface nsIImapMailFolderSink : nsISupports {
   attribute boolean folderNeedsACLListed;
   attribute boolean folderNeedsSubscribing;
   attribute boolean folderNeedsAdded;
-  attribute boolean folderVerifiedOnline;
   attribute unsigned long aclFlags;
   attribute long uidValidity;
   /**
diff --git a/mailnews/imap/src/nsImapIncomingServer.cpp b/mailnews/imap/src/nsImapIncomingServer.cpp
index 30ebb1d0f15a..126df1b9f04b 100644
--- a/mailnews/imap/src/nsImapIncomingServer.cpp
+++ b/mailnews/imap/src/nsImapIncomingServer.cpp
@@ -1722,9 +1722,9 @@ NS_IMETHODIMP  nsImapIncomingServer::FolderVerifiedOnline(const char *folderName
     rv = rootFolder->FindSubFolder(nsDependentCString(folderName), getter_AddRefs(aFolder));
     if (NS_SUCCEEDED(rv) && aFolder)
     {
-      nsCOMPtr<nsIImapMailFolderSink> imapFolder = do_QueryInterface(aFolder);
+      nsCOMPtr<nsIMsgImapMailFolder> imapFolder = do_QueryInterface(aFolder);
       if (imapFolder)
-        imapFolder->GetFolderVerifiedOnline(aResult);
+        imapFolder->GetVerifiedAsOnlineFolder(aResult);
     }
   }
   return rv;
diff --git a/mailnews/imap/src/nsImapMailFolder.cpp b/mailnews/imap/src/nsImapMailFolder.cpp
index 39b85d0bc5d0..963853bc8742 100644
--- a/mailnews/imap/src/nsImapMailFolder.cpp
+++ b/mailnews/imap/src/nsImapMailFolder.cpp
@@ -1027,6 +1027,28 @@ NS_IMETHODIMP nsImapMailFolder::GetVerifiedAsOnlineFolder(PRBool *aVerifiedAsOnl
 NS_IMETHODIMP nsImapMailFolder::SetVerifiedAsOnlineFolder(PRBool aVerifiedAsOnlineFolder)
 {
   m_verifiedAsOnlineFolder = aVerifiedAsOnlineFolder;
+  // mark ancestors as verified as well
+  if (aVerifiedAsOnlineFolder)
+  {
+    nsCOMPtr<nsIMsgFolder> parent;
+    do
+    {
+      GetParent(getter_AddRefs(parent));
+      if (parent)
+      {
+        nsCOMPtr<nsIMsgImapMailFolder> imapParent = do_QueryInterface(parent);
+        if (imapParent)
+        {
+          PRBool verifiedOnline;
+          imapParent->GetVerifiedAsOnlineFolder(&verifiedOnline);
+          if (verifiedOnline)
+            break;
+          imapParent->SetVerifiedAsOnlineFolder(PR_TRUE);
+        }
+      }
+    }
+    while (parent);
+  }
   return NS_OK;
 }
 
@@ -7039,20 +7061,6 @@ NS_IMETHODIMP nsImapMailFolder::SetFolderNeedsAdded(PRBool bVal)
     return NS_OK;
 }
 
-NS_IMETHODIMP nsImapMailFolder::GetFolderVerifiedOnline(PRBool *bVal)
-{
-    if (!bVal)
-        return NS_ERROR_NULL_POINTER;
-    *bVal = m_verifiedAsOnlineFolder;
-    return NS_OK;
-}
-
-NS_IMETHODIMP nsImapMailFolder::SetFolderVerifiedOnline(PRBool bVal)
-{
-    m_verifiedAsOnlineFolder = bVal;
-    return NS_OK;
-}
-
 NS_IMETHODIMP nsImapMailFolder::GetFolderQuotaCommandIssued(PRBool *aCmdIssued)
 {
     NS_ENSURE_ARG_POINTER(aCmdIssued);