In reply to Redpoint Tokay:
What temperature did you wash it in? A hot wash might be enough to melt the seam tape glue (very unlikely to have dissolved). But the discoloration is odd...
You didn't buy it on eBay, by any chance (i.e. is it a fake?)
ps. Daz, being a detergent not generally recommended for any water-repellent item. See many threads passim.