I have this problem since i use
vb 3.7 (beta, now RC).
Most of the time this happens on my board is, then users use the WYSIWYG-Editor.
PhotoPost was fixed, as far as i know (after last PhotoPost-Update, it never happend on PhotoPost) Perhaps Chuck can provide us a little fix ;-)
EDIT: Sorry Bob, after watching you Site, i saw you don't use vBulletin.
@Chuck or Michael: Can you please have a look in
vB's WYSIWYG-Editor-integration? THANKS!