SMTP behavior: 553 5.5.2 Bad command format(h)

WTF? can anyone please explain me why must I enclose my
address between the "<>"?

220 cassiopeia.remeyewear.com ESMTP service
helo me.intercom.com.sv
250 cassiopeia.remeyewear.com talking to ip168-243-227-1
.243.227.171])
mail from:postmaster@intercom.com.sv
553 5.5.2 Bad command format(h)
mail from: postmaster@intercom.com.sv
553 5.5.2 Bad command format(h)
mail from:<postmaster@intercom.com.sv>
250 OK - mail from <postmaster@intercom.com.sv>
quit
221 cassiopeia.remeyewear.com connection

Connection to host lost.

http://www.faqs.org/rfcs/rfc2821.html

Because the RFC says you should. Even back in RFC821 this was the
case:

            MAIL <SP> FROM:<reverse-path> <CRLF>

            <reverse-path> ::= <path>

            <path> ::= "<" [ <a-d-l> ":" ] <mailbox> ">"

Simon