Gmail to get IMAP support

Gmail will be rolling out IMAP support to all its users over the next few days. This is great news to some. Currently I’m using my host’s IMAP server and read mail in (Apple’s mail client), so I probably won’t use it much. However, it is great news for Gmail users especially those who want to read mail on their phones (which do not support Java).

I checked and I don’t have IMAP on my account yet, but there are a few things that I wonder about how you can map the IMAP model (folders containing messages) with Gmail’s model (conversations that can have one or more labels). The conversation part I get, each message in a conversation becomes a separate message in IMAP, but how about labels mapping to folders? There are some answers on the Gmail help site, but still I wonder. The problem is that in IMAP, generally, one message is in one folder. However, a conversation in Gmail can have multiple labels. When you login to Gmail through IMAP, you will see the labels as if they were folders. According to this, you can add multiple labels to one message by copying them to another folder. This means that messages will appear in different folders. There’s an “Inbox”, there’s an “All mail” folder and a folder for each label. So if I have a message in my inbox, labeled as “Work” and “Paper”, it will be in 4 IMAP folders: Inbox, All mail, Work and Paper. I wonder, how do IMAP clients deal with this? Will they recognize that these are one and the same message? I’m not an IMAP expert but do they have these messages have unique ids so you they are recognizable as copies? Or will this message appear 4 times in my search result when I search for it in my mail application? Because that would be kind of stupid.