I want to report exactly the same problem, and it's a real nuisance because many of my large photo collection have picked up from somewhere (apparently NOT PM) crazy IPTC dates, mostly with year 2115, and I want to get all these corrected to the EXIF capture date. PM fails to write any capture dates to the IPTC dates, either through the individual photo IPTC dialog or the stationery pad. At the moment my only way of achieving this is individually for each photo in XnView or PixVue, but this would be far too much work and I want to be able to do this as a batch operation on my collection of now over 1,000 photos. Although those programs do batch IPTC editing, they don't allow you to choose which IPTC fields are written in a batch operation, so that one would have all the selected photos given the same caption, objectname and keywords, which is most certainly not what I want.
I wonder if anyone knows a utility which would do this batch operation just for the date for me while I await a fix for this bug in PM. I'm running Windows XP Pro.