iPod touch when abroad - Can I forward plusnet email to Gmail as a copy?

[#1]

I've recently bought a new iPod Touch so I can do email via hotel or cafe wifi when abroad.  Others have pointed out that Plusnet doesn't support password authentication.  I can set up a redirect on the server before I go to send all my Plusnet email to my Gmail account which I believe would be more secure.
Is it possible to configure the settings so that a COPY is sent to Gmail while leaving the message on the Plusnet server, so that I can organise my Plusnet email (via Thunderbird) when I return?  This would let me deal securely with anything urgent while away via Gmail.
Thanks.

[#2]

I think I've answered my own question.  It's best to leave Plusnet alone and do the configuration from the Google end.  Google can be configured to fetch from Plusnet while leaving the message on the PN server.  Also, sending from Google allows the From field to appear as my Plusnet email.

[#3]

PN does support authentication. The username and password is for the default account and not for the mailbox. PN does have the instructions to setup an iphone http://community.plus.net/library/email/setting-up-plusnet-email-on-an-iphone/ ; but I sure that the setting for outgoing mail is wrong for the smtp server  relay.plus.com as I believe this has to be the default account for all mailboxes.