I just contacted the person whom sent me the drawings and they are using AutoCAD 2006 to add their information and they aren't having trouble with the files. There must be something going on between the original program, the 2006 translation and then the 2007 translation. (we're using 2007)
I would assume the original program has been modified to translate into AutoCAD 2004, 2005 and 2006 just fine, but the new ARXs and file format of 2007 haven't been updated in which ever program it is.