BizTalk FTP Adapter Question

Hi, We have NLB at BizTalk and cluster at SQL. We need to receive a file from FTP location 24/7, but the same file is receiving multiple times due to the default behavior of FTP adapter. 

I found the below information from 

 http://msdn.microsoft.com/en-us/library/aa561801(v=bts.20).aspx

FTP protocol does not lock files to ensure that multiple copies of the same file are not retrieved simultaneously when running multiple instances of the FTP receive adapter.To provide high availability for the FTP receive adapter you should configure the FTP receive adapter to run in a BizTalk host instance that has been clustered.

Now I need to run FTP in load balanced BizTalk production servers. Kindly let me know the possible ways. 

Thanks,

KP.