The protocol that has defined e-mail for more than two decades may have a fatal flaw: It trusts you.

SMTP makes that assumption because it doesn't suspect that you're sending a Trojan horse virus, that you're making fraudulent pleas for money from the relations of deposed African dictators, or that you're hijacking somebody else's computer to send tens of millions of ads for herbal Viagra.

Read more: [URL=http://news.com.com/2100-1038_3-5058610.html?tag=fd_lede1_hed]CNet News[/URL].