Yahoo confirmed culprit in Windows Phone data usage overages

Last week, I tore apart Windows Phone feedback packets to determine the feature’s role in the Windows Phone 7 data usage saga. I didn’t find anything of significant worry there, so I moved onto the next suspected culprit in the list: Yahoo. Sniffing out IMAP packets to and from a Windows Phone isn’t as straight forward as it sounds. Microsoft’s IMAP4 implementation is very aware of the STARTTLS