Activate license on a Linux box via command line

Hello,
I am using OpManager 7 on a Linux box; after installing OpManager in �Professional Edition Trial mode� I used the product adding some nodes and creating some views. I was not able to get the official license before the expiring of the trial period so, at the moment, when I start the server via command line I got this error:

ERROR CODE : 485
Invalid License File
Please contact
AdventNet, Inc.

I do not know how to load the xml license file: I tried to search some solution in the KB and in the forum, but I have not found anything suitable for my trouble.

Could you help me in installing the license using the command line, or please let me know how to load the xml license file in other way?

Thanks in advance

Luca