You should be able to see more by selecting 'Enable debug logging' on the account setup page. However, in this case we may stop reading once the error occurs so you may not see the line with the problem. If you want to dig even further you could use WireShark (or your favorite pcap utility) to obtain a capture.
From what I can tell in your log it looks like we are expecting to find a space and then more content after an attribute but found the end of line instead.
I have opened
Bug 53453 - IMAP readAttributes() fails if space is missing after attribute, feel free to add details to the bug if you find anything more.