Here is a workaround until Autodesk can fix this.
Attached is the file acad2008doc.lsp, in a ZIP file. It loads every time you use Autocad Mech. I added some LISP code that sets ATTDIA to zero.
The file is usually found in the folder C:\Program Files\Autodesk\ACADM 2008\Support.
You can copy the attached file to that location and replace the existing copy, or you can edit the existing copy yourself and add this line to the end of the file...
(command "ATTDIA" "0")
I am a LISP programmer for more years than I care to think about, and I often add snippets of code to address issues like this.
CrAzY-MiKe
Michael Hollingsworth
CAD Administrator | Flexicon Corporation
Autodesk Product Design and Manufacturing Collection 2021