Unable to mount USB drive

Hi
I have mini 2440 running Android (kernel 2.6.27) on it.
When I plug-in USB drive, the drive is detected and I get the following
output on the dmesg.

scsi 0:0:0:0: Direct-Access     Kingston DataTraveler II  PMAP PQ: 0 ANSI:
0 CCS
sd 0:0:0:0: [sda] 2014208 512-byte hardware sectors (1031 MB)
sd 0:0:0:0: [sda] Write Protect is off
sd 0:0:0:0: [sda] Assuming drive cache: write through
sd 0:0:0:0: [sda] 2014208 512-byte hardware sectors (1031 MB)
sd 0:0:0:0: [sda] Write Protect is off
sd 0:0:0:0: [sda] Assuming drive cache: write through
sd 1:0:0:0: [sda] Attached SCSI removable disk

I'm also able to see the device under /sys/block/sda. But I'm not able to
mount the USB drive (mount -tvfat /dev/sda /mnt fails) as there is no
device in the /dev/sdaX.

Does any one know how to fix this issue?

Seems your kernel support for USB mass storage devices is incomplete. Maybe
you just need to load the required kernel modules or you must re-configure
and re-compile your kernel.

Thanks.
Do you know what kernel module needs to be added? 
Based on my google results, it looks like udev is the missing piece here. 

Can you clarify?

My fault: You already wrote you see the "/sys/block/sda". So it seems the
kernel works correctly.
If you are using static devicenodes, just create the missing devicenode. Or
run (you already found it) "udev" to do this job for you.

Juergen,
Thanks a lot. I just created nodes for sda / sda1 and it worked.

You have been very helpful.