how can refer a system dll's instead of system32 to application path?

i need just redirect system dlls reference into my own dll (this may duplicate of same system dll ,but name only changed)...In my application import dlls refer system32 dlls ,so i change that system32 dll name from import dlls into what i desired to change ,after name changes i put the same dll (copied from system32 & pasted into app dir)into my application dir....now here there is any difficulty ...if occur what are they?...

It's hard to tell what it is you are trying to do. I think that IAT hooking may be what you are actually after.