Hi Savita,
This is possible, however the user needs administrative license and I believe it needs a security role. with ru10 an issue was fixed which allows the ability for other users that don't use CRM assign roles and allocate licenses with an administrative license
which does not count as a full license.
In summary, what you want to do is allow someone to assign permissions without using a full license and with RU10 this should now be available.
Hope this helps
Visit my blog for CRM material, improving performance, kerberos, IFD, development tips, etc. :) http://quantusdynamics.blogspot.com