Problem with RDAC drivers

["Kristjan Hinn - PERH" <Kristjan Hinn regionaalhaigla ee>]

Hello

Im having trouble with installing Redundant Disk Array Controller
drivers in Linux Redhat 4 EL kernel 2.6 i have read readme over and over
again and everything seems to be like readme says but im getting error
while running make install command

make install

make V=1 -C/lib/modules/2.6.9-42.EL/build  M=/root/linuxrdac-09.01.B5.31
MODVERDIR=/lib/modules/2.6.9-42.EL/build/.tmp_versions
SUBDIRS=/root/linuxrdac-09.01.B5.31 modules
make: *** /lib/modules/2.6.9-42.EL/build: No such file or directory.
Stop.
make: *** [mppUpper] Error 2

Im missing something but cant find the mistake in system. Can anyone
please direct me to somewhere i can search the problem or give anykind
of clue what the problem might be.

Thank you
Kristjan Hinn