To install Office 2003 under Wine on Debian, see here: http://verahill.blogspot.com.au/2013/01/307-installing-office-2003-in-wine-on.html
In post 376 I compiled and installed wine 1.5.27. Starting word under wine I noticed that an old mathtype install was now recognised (if not completely functional), and that gave me hope that Equation Editor would be installable.
Here's how to get it up and running
1. Control panel
If you've already installed Office under Wine, try using add/remove programs:
and click on Add/Remove programs, then modify your Office installation. That didn't work for me since my Office install wasn't listed for some reason.
If that doesn't work, then
sudo mount -o loop OFFICE11.iso /mnt wine msiexec /i /mnt/pro11.msi
And start the installation.
Start word, go to Insert/Objects