Diffthis a file with conflicting modeline

[Suresh Govindachar]

Hello,

  I just found out that buffers displaying files with modeline 
  that set foldexpr, fillchars, foldtext, foldmethod=expr and 
  foldcolumn=0 cannot be diffthis'ed.  

  So why not make diffthis ignore any conflicting sets from 
  the modeline?

  --Suresh