Compile 6.4.2 under Redhat5.1

I ran configure using the 'with-x' option in
configure and got an warning:'X11 library '-lX11'
could not be found so TK support will be
disabled',where or what rpm is the -lX11 library
under redhat 5.1?

I'm not sure I even need 'with-x'. Is there a more
extensive description of all the configure options
than what is displayed with 'configure -help'?

Also,
I need to compile postgres with storage blocks
greater than 8K so I can use the polygon type
with large polygons.What file and what define in
the source code do I modify to increase the
storage block size?

Regards,
Kenneth R. Mort <kenmort(at)mort(dot)port(dot)net>
TreeTop Research
Brooklyn, NY, USA