One user feedback that when he draft an email and went to check on Zimbra Calendar for a while, he notice a save a draft prompting. However, there is no message in the draft box. Also, when he attempt to send this email, zimbra prompts No such message error. We have to create a new message to copy and paste the content over to send and remove this "no such message" email.
Is this a known bug? Anyone able to duplicate it? Note that he has attached his vcards in his signature.