Adaptec driver

[PP]

Dear Redhat users,

I ran into a problem when installing a brand new adaptec raid card.
It is Adaptec 2410SA, serial ata based real raid card. I would like to 
use it under Redhat Linux 7.3,
according to Adaptec website, it is supported. The aacraid driver 
provided by Adaptec should be used.
After installing the Redhat 7.3, it was fine, everything was OK. This 
release has the 2.4.18-3 kernel.
However a third party application upgraded the kernel to 2.4.20-28.7. 
(It is true that this kernel supports
the aacraid driver, but this aacraid does not support the 2410SA yet.) 
(At this time there is no chance to use any other linux
installation nor kernel version).
So thanks to this upgrade the kernel is unable to mount root after reboot.

I've tried to compile a new driver (provided by Adaptec) which supports 
the 2410SA, but it did not solve the problem.
Here is what I did:
- get and install the sources of 2.4.20-28.7
- make mrproper
- make oldconfig
- make dep
- make clean
- make modules SUBDIR=drivers/scsi/adaptec (since no need to compile any 
other stuff)
This was successful, however in the aacraid.o the kernel version is 
"2.4.20-28.7custom"
Then reboot, insmod fails to load this due to mismatched kernel version.
If I force insmod to load it I get a bunch of errors about unresolved 
symbols.

At the other hand someone has suggested not to compile, but binary edit 
the appropriate aacraid.o
It is true there is a modules.equiv file on the driver disk which tells 
it, but how ?

How do I proceed further ?

Any help would be appreciated
Thanks
Liszli