When (re)listing, eBay wants to verify identity. It's a simple 1-minute procedure.
I did a cleanup on my computer today (CCleaner) and deleted all cookies, temporary files, etc. 10GB of junk gone. However, I don't remember this process when cleaned up last time.
It's little annoying but I understand the protection behind it. Basically if someone hijacks my account, they will still not be able to list.
How long has this been on ?