I can't post in the guide section, so if someone wants to move it there...

Building dosbox on Ubuntu (whatever architecture) is actually pretty trivial (once it's been done once)

Disclaimer: I've had the dependencies (read as what you need to build dosbox) installed for years, so if I forgot one, let me know.

This whole process can be fully automated with a bash script btw...

So, to make it extra simple, this will make a dosbox folder in your home folder.
Fire up a terminal, (it should start in ~) and just cut n' paste

1sudo apt-get install cvs build-essential autoconf automake
2sudo apt-get build-dep dosbox
3cvs -z3 -d:pserver:anonymous@dosbox.cvs.sourceforge.net:/cvsroot/dosbox co -P dosbox
4cd dosbox
5./autogen.sh
6./configure
7make
8sudo make install

That's all there is to it.

If you have a dual-core use
make -j3
or quad-core
make -j5

Instead of just make, to compile in parallel.

To update the cvs and rebuild, fire up terminal:

1cd dosbox
2cvs update
3./autogen.sh
4./configure
5make
6sudo make install

I followed the steps as I wrote this, so it's something that can be done in a few minutes or less. Have fun with the CVS version!