Hi,
I've fixed the problem. We were putting the IPTC date/time into the XMP/Exif "DateTimeOriginal" and "DateTimeDigitized" fields and I just removed this code so that it will leave these XMP fields unmodified.
This fix will be in the next build.
As a workaround, it seems that if you have your "IPTC Info Date and Time uses:" preference set to "Capture Time" then it would match what value you would have had in this XMP field (i.e. the Exif capture time), assuming your IPTC is up to date of course.
--dennis