If CODING-SYSTEM is nil or omitted, the default depends on OBJECT. ... If OBJECT is a string, the most preferred coding system (see the command `prefer-coding-system') is used.
So lj-md5 should use lj-coding-system, but not prefer-coding-system.
This trivial patch fixes wrong behaviour of the lj-md5 function.
April 17 2006, 16:24:32 UTC 6 years ago