At first glance, everything they talk about can be done using IMAP and makes more sense to implement client-side than server-side/embedded into the pr

At first glance, everything they talk about can be done using IMAP and makes more sense to implement client-side than server-side/embedded into the protocol Take a stab at building an unicode-enabled email client that works using 90% of available client features across any one major email provider and any one imap OSS server. After a few months when the flow of edge-case bugs slows to a medium roar, take a stab at allowing customers to connect to a different OSS imap server. Then try adding support for exchange's imap. The standards exist, but they are open to a lot of interpretation in key areas. As a result, there are a lot of interpretations. It's a painful thing.