Service tax query

ours is a construction comapny , we provide construction services to real estate devlopers . we are charging service tax from the client and paying the liability by taking 67 % abatement i.e. no cenvat credit taken. one of our sub contractor is charging service tax on the services provided to us and claims the amount to file his service tax return. my question is when we are paying service tax on the service , won't it will be considered as doubly taxed if our sub contractor pays the service tax on services provided to us . pls advice?