Cause

If you upgrade from one stable SCIM release to another one (for example, from 1.2.x to 1.4.x), you may encounter the issue, especially when you upgrade using source tarballs.

This is because, between different stable releases, SCIM may not maintain IMEngine binary compatibility.

Solution

Recompile/reinstall all scim related package, including all scim-* and skim. Restart your X and it should back to normal.