in monitor.c in MonitorMenu function:
 button = gtk_dialog_add_button (GTK_DIALOG (monoptions),
                                     "Ac_tions", GTK_RESPONSE_NONE);
should be 
 button = gtk_dialog_add_button (GTK_DIALOG (monoptions),
                                     _("Ac_tions"), GTK_RESPONSE_NONE);

Also in logview.c in CreateMainWin() function:
 column = gtk_tree_view_column_new_with_attributes (column_titles[i],
                    renderer, "text", i, NULL);
should be 
 column = gtk_tree_view_column_new_with_attributes (_(column_titles[i]),
                    renderer, "text", i, NULL);