If the server resolves your hostname there's nothing you can do about it I'm afraid. You cannot make it not resolve it.
Check out the network's #Help channel and see if the network you use supports vhosts - some networks do, so that when you set a mode (usually +x) your hostname/IP will be covered up with something like "users.network.org".
If they don't (and most don't) then you might look into purchasing a shell account with a BNC/vhost package of some sort. I can't suggest any personally, but search
Google.
Hostnames shouldn't (to the best of my knowledge) give out your exact home address. Mine is fairly revealing, it gives an abbreviated version of the town I am in (
stev3-3-0-cust174.
lutn where stev is Stevenage, the town I actually live in, and .lutn being Luton, a town near here). Still, although I don't personally care, I can completely understand why some do - but the above two suggestions are the only real options I can think of.
Best of luck!
Regards,