How to install Bricscad V11 on Ubuntu 12.04 LTS

Bricscad V11 has a syntax problem in the description field of the .deb file. This problem causes a failure during the upgrade to Ubuntu 12.04 but it also makes the installer unusable in clean installations of Ubuntu 12.04. The fix is quite simple and similar to the DraftSight on Ubuntu 12.04 64bit workaround.
You have to edit the control file inside the .deb installer. Here is the complete workaround:

Step 1. Move the .deb file into your home folder. Just for simplicity.

Step2. Open a terminal and type:

ar x Bricsad_full_name.deb control.tar.gz

where Bricscad_full_name the full name of your Bricscad .deb installer. Keep the terminal open.

Step 3: Extract the control.tar.gz. file. You will see a folder named control created into your home folder.

Step 4. Edit the control file inside the control folder with gedit. You have to make 2 changes. The first is to change the architecture field from all to i386. This is not necessary but it's preferred for Ubuntu 12.04 even for 64bit installations. The second change is that you have to put a full stop character at every empty line of the description field after the space character that already exists. Every empty line has to be a space character followed by a full stop character. After both changes save the file.

Step 5: Select all the contents of the control folder and compress them as a control.tar.gz file inside your home folder.

 Step 6: Move back control.tar.gz file inside the deb installer. In the terminal type:

ar r Bricsad_full_name.deb control.tar.gz

Step 7: Install and enjoy !!!