* m4/python.m4 (AM_PATH_PYTHON): Fix the invocation of AC_PATH_PROGS to correctly define PYTHON as `:' when no interpreter is found (this worked correctly only when a minimal version was passed to AM_PATH_PYTHON). Report from Stepan Kasal. (_AM_PYTHON_INTERPRETER_LIST): Define using m4_define_default, so we can easily override the list from the test suite. * tests/python11.test: New file. * tests/Makefile.am (TESTS): Add python11.test.