My boss's Blackberry lets him connect to the internet and send email through our exchange server. I would think he could connect to yahoo as well....
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Facile remedium est ubertati; sterilia nullo labore vincuntur. I think pearls are lovely, especially when you need something to clutch. ~ AzTheta
The Real World Can't Hear You ~ GC Troll
I have my homepage on my phone's browser set to my yahoo mail. He may have found your e-mail address somewhere and saved it to his address book, which a spammer then used to send the email.