Hello all, just a heads up. I spent all night tracking this one down. Installing the new spiders.txt from v1.3.9 disabled my google checkout merchant calculated shipping callback. The user would end up in google checkout with no shipping methods available. After debugging the responsehandler and the call to UPS shipping line by line I got nowhere. I finally noticed in the google checkout readme a line about allowing spiders to create sessions, or removing anything like 'jakarta' in the spiders.txt. Allowing spiders to create sessions fixed my problem, but I didn't want to leave it like that, and removing 'jakarta' from the spiders.txt didn't fix the problem. I finally put the old pre-v1.3.9 spiders.txt back in place, and it worked, and I could leave the option for spiders to create sessions to false. I don't know which line(s) in the new spiders.txt is causing the problem. Wow, this was a tough one to find.