imap-enable-exchange-bug-workaround

imap-enable-exchange-bug-workaround is a variable defined in `imap.el'.
Its value is

nil

Documentation:
Send FETCH UID commands as *:* instead of *.

When non-nil, use an alternative UIDS form. Enabling appears to
be required for some servers (e.g., Microsoft Exchange 2007)
which otherwise would trigger a response 'BAD The specified
message set is invalid.'. We don't unconditionally use this
form, since this is said to be significantly inefficient.

This variable is set to t automatically per server if the
canonical form fails.