Samba 4 functional levels

[Aaron E.]

  I need to raise the forest and domain functional level to 2008, I use 
the "samba-tool domainlevel raise" but it doesn't seem to be raising the 
levels... is there another way ? I need this for TS Session Broker to work..

samba-tool domainlevel show output
Forest function level: (Windows) 2003
Domain function level: (Windows) 2003
Lowest function level of a DC: (Windows) 2008 R2

My TS servers show that it is a windows 2003 domain. I cannot raise the 
domain through windows as it says I don't have the proper privileges.

How can I raise this?

Thanks in advance !
Aaron