[Agda] Problems trying to build Agda

[Geoffrey Alan Washburn]

I grabbed Agda 2.1.2 from the wiki, installed and built the packages it 
depends upon, and then started encountering problems.  First, I encountered:

   % runghc Setup.hs build 

   Preprocessing library Agda-2.1.2...
   Building Agda-2.1.2...

   dist/build/Syntax/Parser/Parser.hs:29:0:
        error: ../../undefined.h: No such file or directory

I was able to fix this by manually copying undefined.h into the place it 
was expected (dist/build).  However, I am now stuck on:

   % runghc Setup.hs build 

   Preprocessing library Agda-2.1.2...
   Building Agda-2.1.2...

   src/full/AgdaMain.hs:15:17:
       Could not find module `Data.Map':
         it is a member of package containers-0.1.0.1, which is hidden

I am using GHC 6.8.2.