Hello Kiran,
Currently you are not allowed to use Solution Manager shared for different sap customers ( companies), It's is possible as indicated by friend Prakhar Saxenabut you are not allowed due to usage rights.
There is a Pilot program named SMaMS Solution Manager as Managed Service where there we are testing that types of scenarios, currently for provide SAP license service as self-service to different sap customers with ITSM ( OSS message ), Maintenance Optimizer, Solution Documentaion and SAO engagement and service delivery. check that link:
Solution Manager Project to watch in 2014
Another problem for your scenario is the ise of ITSM for a non-SAP components, to do that you need to check ITSM license prince because non-SAP systems are not included normally (check with your account manager at SAP).
Technically is hard to separate data on Solution Manager, but is possible in different ways, is not easy.
If you need more information related don't hesitate to contact me.
Regards,
Luis