xp's partitions problem

[Pedro]

Hi
i have 2 hard disks,
in the first HD i have 3 partitions
- Partition 1 - Windows XP Pro 1 - user "worker"
- Partition 2 - Windows XP Pro 2 - user "tester"
- Partition 3 - Just Data (share data across both Xp's)

I installed Mandrake Linux in the second HD.

The problem:
Win XP1 works ok.
But, when i enter in the XP2 i cannot log in with user "tester" as
allways... but... i must log in with user "worker" (from the partition 1)

user "tester" has disapeared from the 2nd XP (but the documents and
settings user folder remains on the c drive)

when i log in with "worker" ... i got a lot of errors because the XP2
does not have registry data, documents ans settigs .. etc .. for user
"worker"

If i create a user in the 2nd partition, the user is inserted also in
the 1st partition

How can this happend? where are the user information stored? why the
users are shared across different xp's in different partitions?

thank you-