I followed this thread because I am having similar problems with both the Transformer and a Galaxy Note. I am using K9 mail on each of them. My ISP is Tiscali.
I have no trouble with incoming email, where the POP3 server is pop.tiscali.co.uk
Outgoing mail will not work however on either device.
The SMTP server is smtp.tiscali.co.uk on Port 587 but each time that I try to complete the setup routine I get the message "unable to open connection to SMTP server"
If I continue through this error, I can receive emails without difficulty but attempts to send them just puts them into the draft folder.
I would be very grateful for some guidance.