"I am not able" is not a useful problem description.  It does not say
what you did.  It does not say what happened when you did it.  As usual,
showing actual commands with their actual output can be more helpful
than vague descriptions or interpretations.

> I have a rx 4640 server with hp-ux 11.31.

   Interesting, but incomplete.  FTP normally involves two systems: a
client and a server.  What are your _two_ systems?  Which is the client,
and which is the server?

> I am doing it in passive mode only.

   You are doing _what_, exactly?  My psychic powers are too weak to
tell me what "it" is.