WCF: When the client timeout is shorter than the service timeout

WCF: When the client timeout is shorter than the service timeout

I have an question. I wrote a WCF in my server and got a problem about
timeout. Father, I wrote a client to test my service.
Then, I assumed that I don't know how long is the client's timeout, so I
set my service timeout as 300(s).But actually, my client's timeout is
5(s).
So, when I run my client, it will get the timeout exception like "The
operation has timed out". Can I raise an exception when the client
disconnects in my service?
Thanks a lot. :)