OMA security

[Enrico Mioso]

Hi all!
My question might be a little "stupid" - still: does OMA offer an adequate 
security?
Ok - the solution is proprietary and so it's difficult to understand.
In other words - is the user free to to not accept a network initiated DM 
session? If for example the user doesn't want to have a certain feature 
disabled  /  software upgraded?
thank you all for the reply!