fc 3 insatllation error assertion(head<256)

[ban]

hey guys i'm just vry new into linux world. i have window xp pro in my
system installed. so i use partition magic to create a new space for
linux(fc3) installation. the disk size i kept for linux is 20gb. when i
install it i got this error assertion(head<256) at disk_dos.c:486 in
function probe_partition_for_geom() failed. when i keep pressing ignore
it proceed but stop when i come to the part for assigning partition
size using disk druid. dont want to remove xp and recreate a new
partition for the installation. help me out.