Might have something here. In po-preset-string-functions (in po-mode.el) there is the following: (let ((pair (cond ... ... ((member mode-name '("C" "C++")) '(po-find-c-string . po-mark-c-string)) ... When my emacs loads C code, electric mode is enabled and therefore the mode name is 'C/l', not 'C'. Therefore, po-preset-string-functions does not select the correct po-find-... and po-mark-... functions.
What do you think? I will investigate further. Pete