AC_ARG_ENABLE(flock, AC_HELP_STRING([--enable-flock], [Use flock() to lock files]),
[if test $enableval = yes; then
AC_DEFINE(USE_FLOCK,1, [ Define to use flock() to lock mailboxes. ])
AC_ARG_ENABLE(flock, AC_HELP_STRING([--enable-flock], [Use flock() to lock files]),
[if test $enableval = yes; then
AC_DEFINE(USE_FLOCK,1, [ Define to use flock() to lock mailboxes. ])