[itsm] Linking services to customers

[Paul Rhein]

Hi list,

Base: otrs 2.2.4. and the itsm 1.0.4 modules. I am preparing a 
presentation of the ITSM features in OTRS.
I would like to create tickets in phone view and use the service field to 
assign them to a service.
Digging the archives I found an entry where it says, that to do so, I 
first need to create the services and link them to customers.
I added 'services' in the GUI, and changes to the 
LinkedObject2Services.xml file to have 'customers' as possible partners 
and added some 'link types' too.
So far so good but now otrs complains about the missing files 
'../LinkedObject2/Customer.pm', so I wondered if need to code all those 
files to be able to link customers to services ? Has somebody done this 
before ? Do I miss a crucial point ? Is there a howto ?

Any help welcomed.

thx

Paul