[root@localhost asterisk]# ./configure
checking build system type... i686-pc-linux-gnu
checking host system type... i686-pc-linux-gnu
./configure: line 1467: AC_USE_SYSTEM_EXTENSIONS: command not found
checking for uname... /bin/uname
checking for gcc... gcc
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables...
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ANSI C... none needed
checking for g++... g++
checking whether we are using the GNU C++ compiler... yes
checking whether g++ accepts -g... yes
checking how to run the C preprocessor... gcc -E
checking how to run the C++ preprocessor... g++ -E
checking for a sed that does not truncate output... ./configure: line 3799: syntax error near unexpected token `SED,'
./configure: line 3799: `     _AC_PATH_PROG_FEATURE_CHECK(SED, sed gsed,'
[root@localhost asterisk]#