Thank you for your fast answer.
This is my lilo.conf
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lba32
boot=/dev/hda1
root=/dev/hda1

bitmap=/boot/sid.bmp
bmp-colors=1,,0,2,,0
bmp-table=120p,173p,1,15,17
bmp-timer=254p,432p,1,0,0

install=/boot/boot-bmp.b

prompt
timeout=50
map=/boot/map
vga=normal

image=/vmlinuz
label=Linux
read-only

other=/dev/hdb1
label=Xp
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As you can see it reflects my system's configuration(as reported above)
It keeps being strange that xp doesn't load.

If you can find something wrong ,please let me know.
I need your help.
I tried /sbin/lilo as root with no results.