Original MAC OS X ppd driver - LexmarkE120n.ppd 

Patch to work on linux - lex-e120n-linux.patch 

Save files without .txt suffix and run

  • patch -p0 < lex-e120n-linux.patch
  • gzip -c LexmarkE120n.ppd > /usr/share/cups/model/lex120n.ppd.gz

and restart cups.