Weird 64 bit ruby error

Hello,

I am trying to build ruby 1.8.6 on my RHEL 5 64bit Intel box for a
rails
application server. When trying to build readline I get the following
error
, any ideas ?

/usr/bin/ld: skipping incompatible /usr/lib/libncurses.so when searching
for
-lncurses
/usr/bin/ld: skipping incompatible /usr/lib/libncurses.a when searching
for
-lncurses
/usr/bin/ld: skipping incompatible /usr/lib/libdl.so when searching for
-ldl
/usr/bin/ld: skipping incompatible /usr/lib/libdl.a when searching for
-ldl
/usr/bin/ld: skipping incompatible /usr/lib/libcrypt.so when searching
for
-lcrypt
/usr/bin/ld: skipping incompatible /usr/lib/libcrypt.a when searching
for
-lcrypt
/usr/bin/ld: skipping incompatible /usr/lib/libm.so when searching for
-lm
/usr/bin/ld: skipping incompatible /usr/lib/libm.a when searching for
-lm
/usr/bin/ld: skipping incompatible /usr/lib/libc.so when searching for
-lc
/usr/bin/ld: skipping incompatible /usr/lib/libc.a when searching for
-lc
/usr/bin/ld: skipping incompatible /usr/lib/libc.so when searching for
-lc

Thx
Adam