I was trying to install libxml2 on OSX 10.6.3 using mac ports.
sudo port install libxml2
Macports died with an error
Error: Unable to open port: invalid command name "livecheck.type"
livecheck.type seems to be a new command in Macports 1.8.0. Upgrading to Macports 1.8.0 solves the problem.
To upgrade use
sudo port selfupdate
Dont forget you’ll need to install Xcode or you’ll get this error message
configure: error: in `/opt/local/var/macports/sources/rsync.macports.org/release/base':
configure: error: no acceptable C compiler found in $PATH
See `config.log' for more details.