Readline extension doesn't compile with ruby-1.8.4 on RedHat

Hi,

I am basically following this guide:

and do

curl -O ftp://ftp.gnu.org/gnu/readline/readline-5.1.tar.gz
tar xzvf readline-5.1.tar.gz
cd readline-5.1
./configure --prefix=/usr/local
make
make install

fine. Then

curl -O ftp://ftp.ruby-lang.org/pub/ruby/1.8/ruby-1.8.4.tar.gz
tar xzvf ruby-1.8.4.tar.gz
cd ruby-1.8.4
./configure --prefix=/usr/local --with-readline-dir=/usr/local
make
make install

fine too. I don’t get any errors. But

$ ls -w 20 /usr/local/lib/ruby/1.8/i686-linux/.so
bigdecimal.so

dbm.so*
digest.so*
dl.so*
enumerator.so*
eruby.so*
etc.so*
fcntl.so*
iconv.so*
nkf.so*
openssl.so*
pty.so*
sdbm.so*
socket.so*
stringio.so*
strscan.so*
syck.so*
syslog.so*
tcltklib.so*
tkutil.so*
zlib.so*

No readline.so in there. What am I doing wrong?

Here is the part of the output where it says it compiles, but it
actually
doesn’t:

compiling racc/cparse
make[1]: Entering directory
/usr/src/install/ruby-1.8.4/ext/racc/cparse' make[1]: Nothing to be done for all’.
make[1]: Leaving directory /usr/src/install/ruby-1.8.4/ext/racc/cparse' compiling readline compiling sdbm make[1]: Entering directory /usr/src/install/ruby-1.8.4/ext/sdbm’
make[1]: Nothing to be done for all'. make[1]: Leaving directory /usr/src/install/ruby-1.8.4/ext/sdbm’
compiling socket

$ find /install/ruby-1.8.4 -name *.so
./.ext/i686-linux/bigdecimal.so
./.ext/i686-linux/dbm.so
./.ext/i686-linux/digest.so
./.ext/i686-linux/digest/md5.so
./.ext/i686-linux/digest/rmd160.so
./.ext/i686-linux/digest/sha1.so
./.ext/i686-linux/digest/sha2.so
./.ext/i686-linux/dl.so
./.ext/i686-linux/enumerator.so
./.ext/i686-linux/etc.so
./.ext/i686-linux/fcntl.so
./.ext/i686-linux/iconv.so
./.ext/i686-linux/io/wait.so
./.ext/i686-linux/nkf.so
./.ext/i686-linux/openssl.so
./.ext/i686-linux/pty.so
./.ext/i686-linux/racc/cparse.so
./.ext/i686-linux/sdbm.so
./.ext/i686-linux/socket.so
./.ext/i686-linux/stringio.so
./.ext/i686-linux/strscan.so
./.ext/i686-linux/syck.so
./.ext/i686-linux/syslog.so
./.ext/i686-linux/tcltklib.so
./.ext/i686-linux/tkutil.so
./.ext/i686-linux/zlib.so

-Sascha E.