Stop Apple Mail from uploading deleted iCloud draft

I posted this under Snow Leopard as well (for Apple Mail client):

I created a new mail in my iCloud/me account and attached a photo only to realize I accidentally attached the original 107MB Photoshop file instead of the 401KB JPEG I intended to attach. While Apple mail is busy connecting to the mail server, I deleted the attachment and eventually deleted the draft. Apple Mail seems to be determined that it still has this task to do to upload this file - the activity pane in Mail and Little Snitch are showing me this seemingly endless upload happening. Is there anything I can do to stop it? I logged into the iCloud web interface and deleted the draft there as well to no avail. All of this is using Apple Mail client on Snow Leopard with iCloud/me.com account using IMAP settings.