[Click] How can I install the e1000 driver

[netlee1010]

I am a novice . I have bought two NICs and the chip is intel 82540EM  . 

but when I install the driver in the $CLICK/driver/e1000-7.x/src,  there are some errors

lili at linux:~/click-1.7.0rc1/drivers/e1000-7.x/src$ make
make -C /lib/modules/2.6.27-7-generic/build SUBDIRS=/home/lili/click-1.7.0rc1/drivers/e1000-7.x/src modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.27-7-generic'
scripts/Makefile.build:46: *** CFLAGS was changed in "/home/lili/click-1.7.0rc1/drivers/e1000-7.x/src/Makefile". Fix it to use EXTRA_CFLAGS.  Stop.
make[1]: *** [_module_/home/lili/click-1.7.0rc1/drivers/e1000-7.x/src] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.27-7-generic'
make: *** [default] Error 2

my kernel is 2.6.24.7 with click patch