Testing Citrix based application to support 50 users load

The customer want us to do a performance testing of their application, which is hosted in Citrix , giving an user load of 50...but they won't be able to give access to 50 test userids to their application: 2 to 3 testuser id's can only be given access to the application to be tested.

Is there any way to simulate 50user load on the application using only limited number of test user ids...even I hav heard that there are some restrictions on the number of sessions an user can have in Citrix

Please suggest