smtp.SendMail无法将邮件发送到多个配方golang

I want to send mail to multiple recipients in Go, with my yahoo mail, but I from all recipients only I get mail.

Code:

err := smtp.SendMail(
    "smtp.mail.yahoo.com:25",
    auth,
    "testmail1@yahoo.com",
    []string{"testmail1@yahoo.com, testmail2@yahoo.com"},
    []byte("test")

message:

From: "testMail1" <testmail1@yahoo.com>
To: testMail1 <testmail1@yahoo.com>, testMail2 <testmail2@yahoo.com>,
Subject: "mail"
MIME-Version: 1.0
Content-Type: text/html; charset="utf-8"
Content-Transfer-Encoding: base64

This is output:

2015/05/18 20:22:26 501 Syntax error in arguments

What have I done wrong?

Your code snippet is incomplete and does not match your email. Could you send more code?

Anyway you can try replacing:

[]string{"testmail1@yahoo.com, testmail2@yahoo.com"},

By:

[]string{"testmail1@yahoo.com", "testmail2@yahoo.com"},

Also you can try my package Gomail to easily send emails:

package main

import (
    "gopkg.in/gomail.v2"
)

func main() {
    m := gomail.NewMessage()
    m.SetAddressHeader("From", "testmail1@yahoo.com", "testMail1")
    m.SetHeader("To",
        m.FormatAddress("testmail1@yahoo.com", "testMail1"),
        m.FormatAddress("testmail2@yahoo.com", "testMail2"),
    )
    m.SetHeader("Subject", "mail")
    m.SetBody("text/plain", "Hello!")

    d := gomail.NewPlainDialer("smtp.mail.yahoo.com", 25, "login", "password")
    if err := d.DialAndSend(m); err != nil {
        panic(err)
    }
}