i went into my yahoo account on my pc only to find that i sent 100s of copies of a reply to an email to 2 different people. I am also missing many messages that i deleted on the phone, but not on the pc.
i am also having problems sending email in general- things get hung up in the oputbox, even when i push send (tho i'm afraid to do that right now, for fear of sending a million copies).
i was so loving this phone too.....
I found a little app in the Android market called ROID. It seems to do a nice job of getting yahoo mail, even if I have Wi-Fi enabled. Definitely worth the two bucks.