Setting Deleted flag on message in Gmail folder throws Protocol Exception

[brettmarl]

Relevant code is:

ImapClient c = new ImapClient();
c.Connect("imap.gmail.com", 993, true);
c.Authenticate(...);

var folderSrc = c.GetFolder("[Gmail]/All Mail");
folderSrc.Open(FolderAccess.ReadWrite);
for (int i = 0; i <folderSrc.Count; i++)
{
    var message = folderSrc.GetMessage(i);
    folderSrc.AddFlags(i, MessageFlags.Deleted, false);
}

AddFlags throws a protocol exception:
[MailKit.Net.Imap.ImapProtocolException] {"Unexpected token in IMAP response: [atom: 0]"}
HResult = 0x80131500

Protocol Logger says:

C: A00000009 STORE 1 +FLAGS (\Deleted)
S: * 1 FETCH (FLAGS (\Deleted) MODSEQ (0))
S: A00000009 OK Success

Server is Gmail on a Google Apps domain.

[jstedfast]

The problem is that the modseq value is not allowed to be 0 according to the specs:

   fetch-mod-resp      = "MODSEQ" SP "(" permsg-modsequence ")"
   permsg-modsequence  = mod-sequence-value
                          ;; per message mod-sequence
   mod-sequence-value  = 1*DIGIT
                          ;; Positive unsigned 64-bit integer
                          ;; (mod-sequence)
                          ;; (1 <= n < 18,446,744,073,709,551,615)

[brettmarl]

sweet - that a quick - thanks.