[Evolution] exchange ics calendar integration broken?

[Reid Thompson <jreidthompson nc rr com>]

Git head - exchange owa.
anyone else experiencing this, i've been experiencing it for several
weeks at least:

Meeting requests from exchange (ics) are not able to be added to the
calendar.  All requests that I get show in the preview pane with
all selection buttons inactive and the text
    Searching for an existing version of this appointment
The calendar communications appear to be active, i.e.
selecting/deselecting the owa calendar causes previously defined
appointments (repetitive events that were set months ago) to
appear/disappear.