Current ZMail IMAP Workaround!
Staying within the confines of the existing ZMail system, I think I have come up with a work around that is good (and will soon be better).
Using ZMail as your default inbox is great, but the problem with sent mails is that they don't show up (and I send a lot of email from my handheld to clients).
Furthermore, I often do have to send attachments, and as a time saver I like the ability to drag and drop attachments into an Outlook email (I just don't have the patience to upload attachments to outgoing emails with "browse and click" method.)
Here are the steps for the workaround:
1 - create a new folder in ZMail called "Sent Items" (I know there is already a sent folder, but this is another glitch that I'll address in a minute)
2 - create a filter such that every email brought into ZMail via POP where the sender is you, gets filtered to your new "Sent Items" folder (The glitch is that ZMail can't filter OR move any emails to the default sent folder, I hope they correct this soon)
3 - Now you're all set up. Whenever you send an outgoing message from Outlook or your Handheld (iPhone, Blackberry, etc) just Cc or Bcc yourself on the email. If you Cc/Bcc yourself, ZMail will pickup the email from the POP as an incoming message, but instead of going into your Inbox, it will get filtered to your "Sent Items" automatically and if you want you can have it marked "as read" on arrival.
---There you go, it's not perfect, but it gets all emails you send from Outside of ZMail into Zmail very simply. Hopefully Zoho will correct the glitch that won't allow you to filter or move emails into your default Sent Items soon and it will be even better.
Hope that helps!
-James