"Stephen J. Turnbull" <turnbull(a)sk.tsukuba.ac.jp&gt; writes: Yes. And now do it such that all of the following are true (which they currently are). 1. Loading the .elc is fast 2. The .el file is used by both versions. 3. The .elc can be used by both versions. Having a conditionally compiled in mule is good however it makes things like this hard. Basically the will need to be some load time character set conversion defined such that it is the identity on latin1 XEmacs. Doing this fast will probably make the code ugly. Jan