sybase IQ 15 installation of RedHat 6 - Java error

Hi

I get the following error when I run setup.bin -I console :

Stack Trace:

java.lang.UnsatisfiedLinkError: /tmp/install.dir.3524/Linux/resource/jre/lib/i386/xawt/libmawt.so: libXext.so.6: cannot open shared object file: No such file or directory

which Linux package contains these libraries?  Your help is very much appreciated.

thanks

CS