There is a bug in waf that prevents serializing the sudo commands used during --enable-sudo in emu and tap.  Gustavo has reported the bug and is awaiting a response.  This manifests itself as an inability to enter a correct password since two sudo instances are running at the same time.  There are workarounds,

0) If you don't know what I'm talking about, chances are this won't affect you;

1) If you don't use emu or tap, don't worry about it;

2) If you run your simulations that use emu and tap as root, you won't be affected; just don't --enable-sudo and don't worry about it;

3) If you run your simulations that use emu and tap as a regular peon user, the workaround is to get yourself a sudo ticket before you try to build the socket creators.

For example,

  sudo ls
  ./waf