[Samba] access and rights problems

[ianux]

I have a problem with share permission
I have a [homes] section (untouched from smb.conf.default) and other
shares
security is set to DOMAIN
when my users try to access samba, they see shares and their home named
as their NT login name
they can look into shares, but to access their home, windows ask them
user/password. But It has been already sent, as their home appears as
their login name
another thing : they can't write in shares, although writeable=yes is
set, unless I chmod a+w directories...
 I uses samba-latest, from source. Do I missed a configure option ?