dual grub install?

[Hugo Bodewig]

Hi everyone,
recently I upgraded to Ubuntu 12.04. Since I had a previous version I
decided to wipe the partition and do a clean install on sdb.

My set up is as follows
sda contains all windows stuff and on sda1 the boot sections
sdb contains only Linux
Previously on booting grub showed Linux / Linux recovery / Mem Test /
Win 7 on sda1

After installation of Ubuntu 12.04 I have
Linux / Linux recovery / Prev Linux / Mem Test / Win7 on sda1 / Win7 on sda2

Both these Win7 entries are bootable.

The grub looks like this
### BEGIN /etc/grub.d/30_os-prober ###
menuentry "Windows 7 (loader) (on /dev/sda1)" --class windows --class os {
        insmod part_msdos
        insmod ntfs
        set root='(hd0,msdos1)'
        search --no-floppy --fs-uuid --set=root CE769EA1769E89BB
        chainloader +1
}
menuentry "Windows 7 (loader) (on /dev/sda2)" --class windows --class os {
        insmod part_msdos
        insmod ntfs
        set root='(hd0,msdos2)'
        search --no-floppy --fs-uuid --set=root 76B2A189B2A14F05
        chainloader +1
}
### END /etc/grub.d/30_os-prober ##

Question - Why did this happen?
Question is there really a bootloader now on sda2? I did not check the
disk itself

Regards