I was without a Net connection today at one point and needed to run the development server for my Google App Engine app and the server kept getting stuck while trying to check for updates.
The Running the Google App Engine SDK offline without an Internet connection article by Aral Balkan, unless otherwise expressly stated, is licensed under a Creative Commons Attribution-Noncommercial 2.0 UK: England License.
Checking the options for dev_appserver.py, I couldn't find a setting to tell it to stop checking for updates to the SDK.
When back online, some quick googling turned up the existence of an .appcfg_nag file that dev_appserver.py creates after it is initially run. Searching around my computer, I found that the file in question is created in your home folder. A quick rm ~/.appcfg_nag, followed by running the server and telling it not to check for updates remedied the issue.
A simple thing, perhaps, but it does make a big difference in that I can now work while offline with the SDK too.
The Running the Google App Engine SDK offline without an Internet connection article by Aral Balkan, unless otherwise expressly stated, is licensed under a Creative Commons Attribution-Noncommercial 2.0 UK: England License.

thanks for the tip, good to know!
Yeah, it’s anoying when the SDK is up to date all the time hahahahahaha. thanks man.
BTW, in Windows Vista it’s located in C:\Users\{your-user-name}\.appcfg_nag just like .appcfg_cookies.