Im getting the error "configure: error: The client requires GNU readline library 2.1 or newer. Either install the library or use --disable-client to compile without the client." from the configure script on a CentOS 5.6 64bit machine. I have the the readline RPM from the distribution repository as well as the distributions development package: # rpm -qa | grep readline readline-devel-5.1-3.el5 readline-5.1-3.el5 searching the readline header files returns what I think the configure script is checking for: # grep rl_callback_read_char /usr/include/readline/* /usr/include/readline/readline.h:extern void rl_callback_read_char PARAMS((void)); Adding '-I/usr/include/readline' to the CFLAGS doesn't help. I feel like I'm missing something obvious but not sure where to turn. Google has not proven very fruitful. Thanks ryan