Like many other I ran into issues after upgrading to mountain lion (OSX 10.8). The install and upgrade of the OS went smoothly, and the upgrade installed the latest version of xcode.
I ran into issues with macports when I ran an upgrade from the terminal. After the upgrade finished I attempted to upgrade my installed ports in the usual fashion, but the self update failed with permissions problems accessing TCL.
- To fix this issue I downloaded and installed the latest macports build from the DMG installer: macports.dmg for 10.8
Installing macports from the installer package corrected the selfupgrade problem for me. Now I was having issues with building the ports. None of the command line tools were installed with the OS upgrade. With a little digging around the internet I found that the command line tools are now distributed in a separate installer off of developer.apple.com/downloads. Make sure to download the command line tools for OSX mountain lion.
- To fix this issue I downloaded and installed the latest command line tools from developer.apple.com/downloads. You will be required to sign in to download the tools.
Once that was finished, I am able to upgrade all my ports from the command line as you would normally expect.
Hope this helps! your millage may vary.