port install db46
fails badly and complains about dependencies.
The easiest fix is to install it without java (and you don't need java)
sudo port -v selfupdate
port clean db46
port install db46 +no_java
There are other articles about this problem, How to fix db46 problem macport installation
or MacPorts 1.8.2 fails to build db46 on Mac OS X 1.6.3