I am trying to zip a file with password protection.

I have read all or atleast most of the threads on the website, but couldn't come up with a solution.

I am running ZIP version 2.3 on HP-UX but I dont see the -P (password) option. I read somewhere that free versions of zip don't come with -P option. Can someone confirm this assumption. I have already wasted a weeks effort on this.

Can anyone suggest anyway of doing this, we are planning to send out an email (with attachment) to yahoo/gmail/outlook from our UNIX box but the file has to be password protected before it goes out. User will open the attachment from that email.