Java - Too Many Files Open

I understand in Java 1.3.1 or 1.4.x there is a limit of 1024 files that can be opened via java (default), how does one increase this limit to say 4096 (for the session in question)? I attempted to use ulimit -n 4096, but it gives me operation not permitted as my plain old self (reg. user). I have looked at ulimit -n, but it gives me operation not permitted. Also, on machines which are production servers (java, webservers, etc)...what should the value of /proc/sys/fs/file-max be (i've looked for a reliable answer, but nothing has turned up as of yet). -Bill