Reliable copy trader

Hi

I'm looking for a reliable copy trader system I can load on my VPS. Basically I want to do the following :
- I will have a master account
- My clients will have sub accounts to where the signals (buy, sell, close, etc) will be copied to
- I cannot get all my clients on the same broker and server - is there a way to overcome this ?
- Is there a way to adjust for lot sizes ?

If you know of any, please advise.

Thanks

http://www.fxblue.com/