[Samba] Get logged on username

[Kurthermal]

Hello,
I'm writting an application that will be running on a Samba PDC. It has 
to get <login> (%username%) currently logged on some windows NT domain 
clients.
I began to use 'net status sessions' but sometimes it returns more than 
one user currently logged on the same windows client.
What's happening ?
Is there a solution to avoid this ?
Are there other methods to get <login> ?

Thanks,
K.