I am using FreeCompose from https://code.google.com/p/freecompose/ to type german umlaute e.g. ä or ß on us keyboard layout. This works like a charm except in claws mail, where my composition is not entered into any textfield. Reproduction: 1. Open any Dialog in Claws Mail where plain text can be entered, e.g. mail composition. 2. Type <compose-key>"a 3. no ä appears, simply no character at all appears. 4. the sequence in general is processed from freecompose, i guess, because the letters " and a do not appear. Simply the result is somehow suppresed in claws. I am using Shift-Lock as compose key, but have tried others.
Claws Mail is using GTK+ library for its user interface, and there is a bug in GTK+ causing it not to work with FreeCompose. See FreeCompose FAQ: https://code.google.com/p/freecompose/wiki/FreeComposeFAQ Next Claws Mail Windows release (coming soon) will have latest 2.24, which has this bug fixed. I am closing this bug for now, feel free to reopen if the issue persists with the new release.