What Does "expired" mean in GWT?

[watto]

Recently I hired the services of an SEO company who pr sculpted my site with great results, however today I have noticed that a lot of my pages have reappeared in google, pushing the pr back to these pages which we originally scultped. eg:

www. business-trader.com.au/newuser.php ( this page originally had a pr2, then I removed
this url from google in my GWT and disallowed it in my robots.txt in August and was de-indexed and went to a
pr0. Today it now has a pr2 again???)

www. business-trader.com.au /buy_sell_business_result/14778/Sumo-Salad-Franchise.html ( this page was also removed and now has pr2
again)

Most of the pages that have been reindexed start with /buy_sell_business_result.

I did notice that in my "GWT remove urls, 'removed content' section it says:

Aug 25, 2008 www. business-trader.com.au/newuser.php Web page removal "
"Expired" . Why does it say "expired"???

Just yesterday when I did a search this page said site:business-trader.com.au (255) and
now it says (529). Where did these pages come from and how did they reappear?

regards

watto