I have faced this issue about 5 times already with many new registered users having 4 or more billion posts in their count. I do have photopost gallery and photopost classifieds integrated. Along with the integration, I also have the user posts incremented by comments in both the gallery and classifieds script.
I am running on
vb 3.8.2 and photopost pro 6.2.2 and photopost classifieds 3.1. I haven't seen this occur in the last two weeks, and by that time I have also upgraded to
vb 3.8.2. I dont know but its strange how such numbers arise in the first place.