I ran into an oddity the other day, which mentioned 1PW (hence the post in an Agile forum) but may have no actual connection.
I had to go to a Web site that stated, when I used Safari, that a client certificate was required and asked me to select a suitable certificate. But the list of available certificates had only two items in it, 1PasswordAgent and 1PasswordAgent followed by a long string. Neither of them worked, as they had expired in 2009. Looking at Keychain Access, I could see some valid Apple certificates, but they did not appear in the list I was asked to choose from.
I finally was able to use the site via Firefox, which did not ask me for a certificate.