Mr Exotic - thats the reason I wont trade with anyone that comes to me telling me what PR they have - first off - that toolbar is so out of date with PR its not funny - by the time it updates the site itself has had the PR for 3 months usually.
The link/backlink and the PR indicator have both been manipulated by Google on purpose to show incorrect numbers as of 2 years ago so everything garnered from it is useless.
The webmasters that come to me for trades have learned to never mention PR
It will get them shutoff from my end quicker than anything else