I managed to get e-mail, calendar, and contacts sync from Notes to iPhone, I thought I post my solution for those who are interested.
E-mail sync
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First, turn on IMAP on Domino server. Configure iPhone to get e-mails from “Other” and use IMAP server. POP will work as well, except it won’t fetch the folder structure. It won’t have a dynamic push like yahoo e-mail, but it can fetch e-mail every 15 mins which is good enough for me. Also, you can opt to download new e-mails instead of wait for the 15 mins auto fetch.
This works out really well. I can see full richtext e-mails fine. The fact that I can send myself a grocery list speaks for itself!! 
But, the next problem I had is sending e-mails. I have no e-mail relay turned on on Domino so it was rejecting e-mails from iPhone. Once I configure Domino SMTP to allow relay for authentic users and configure iPhone SMTP with user name and password then I was able to send e-mails!
I now have Blackberrish e-mail receive and send on iPhone without installing additional software. That’s way too cool!!
If the company Domino server is behind VPN then this solution can be a problem. Somehow, SMTP and IMAP ports have to be open.
I can also use iPhone’s Safari browser to check Notes e-mail. Except I can’t use iNotes (DWA) cause Safari is not a browser that iNotes supports. However, I was able to use the webmail interface by adding ‘?opendatabase&ui=webmail’
http://domain.com/mail/mail.nsf?opendatabase&ui=webmail
that’s the older internet e-mail access interface if you recall. It’s an ugly interface than iNotes but it works. The toolbar does not work cause it uses java applet (iPhone Safari browser does not support java or flash). But, once I change the act bar properties to use HTML for web access, then I was at least able to send e-mails.
It would be good if IBM/Lotus can make iNotes work on Safari as well, then we can use iNotes on iPhone (lots of 'i’s people like to use!).
Calendar and Contacts sync
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I found a product that would sync Notes contacts and calendar from/to Notes to Outlook. They take advantage of iTunes able to sync from Outlook to iPhone to allow Notes calendar and contacts show up on iPhone.
Basically, it uses Outlook as a conduit. I was able to get contacts and calendar downloaded to iPhone the first round. But, it hangs on subsequent sync. It could be my calendar dates back to R4 and I have many years of calendar entries. Some entries may be corrupted. I don’t know what the problem is. But, at least I got contacts down and somewhat readable calendar entries on iPhone. I suppose I can always do a one way total replacement of contacts and calendar entries on iPhone although that’s more time consuming.
The product is still in beta so they may be able to work out the kinks later.
I should also note that contacts and calendar sync is not wirelessly like e-mails over IMAP. It requires you to use iTune and be connected to your PC.
If you want a only browser solutiont to check your calendar, you can do the same Safari browser trick to access the calendar by adding ‘/CalendarFS?OpenFrameSet’ on the URL,
http://domain.com/mail/mail.nsf/CalendarFS?OpenFrameSet
Again, the interface is not pretty, but if you really have to lookup your calendar over a iPhone browser – you can.
It’d be great if IBM/Lotus can talk to Apple and have it not only to sync to Outlook, but also Lotus Notes.
I hope this is helpful for those looking into buying iPhone.