A Wikipedia user, Matthias Buchmeier, has created an awk script for extracting bilingual dictionaries from the English Wiktionary in dict format. His instructions are slightly confusing for me, but you can download all the dictionaries he has compiled in one 60MB package. Remember that you will need the dict versions of the files.
I'm definitely interested in converting the script to dsl format and/or trying to reproduce this for the French and German dictionaries, but my programming knowledge is extremely basic, so if anyone is interested in taking over or cooperating with me, I would appreciate it.