exception in git-gui when saving options

hoi :)

I get the following backtrace when I want to save options in a git-gui which is started in blame mode:

can't read "current_diff_path": no such variable
    while executing
"set p $current_diff_path"
    (procedure "reshow_diff" line 5)
    invoked from within
"reshow_diff"
    (procedure "do_save_config" line 5)
    invoked from within
"do_save_config .options_editor"
    invoked from within
".options_editor.buttons.save invoke"
    ("uplevel" body line 1)
    invoked from within
"uplevel #0 [list $w invoke]"
    (procedure "tk::ButtonUp" line 22)
    invoked from within
"tk::ButtonUp .options_editor.buttons.save"
    (command bound to event)

The options seem to be saved correctly.