Can't login from windows 7pro to samba3 domain with long username - bug?

[Gennady G. Marchenko]

Hi all!

Is anyone tried to login to the samba3 domain from windows 7pro with 
username longer, then 21 symbols?

System: FreeBSD7
samba: 3.4.9 PDC
Client: Windows 7pro (with sp1 too)

I have tried and it doesn't work :( But with windows XP SP3 all works 
fine. I can't find anything like this in google  - is it bug?

Best Wishes,
Gennady.