If you check my last post and follow the link provided, then click the "-c" link that is fairly obvious near the top of the linked page, where it says:
you will see the -c option in detail and it says:
Unless you can post your question or at least details of the "some where i read tht pwdadm cmd is used to create user without password" to clarify your problem then I don't think we can offer much more useful advice.