Repeat

Here's a slightly simpler procedure for the same workaround:

1. Edit ~/.scim/config and set /FrontEnd/X11/Dynamic = true

2. Make the file immutable: sudo chattr +i ~/.scim/config

3. Logout, login.

4. Make the file mutable again: sude chattr -i ~/.scim/config

I personally choose to skip step 4, so I'm sure it won't be changed without my permission. Be careful with this, because that may become a problem if you forget about the +i or if a future version cannot cope with the current config format.