[squid-users] squid wrong of dns overload

Good morning, Everyone :
Squid a DNS Overload wrong, please look at the help. Thank you very much!
Squid Version: 2.6.STABLE6
May 7 07:18:21 squid squid[2741]: dnsSubmit: queue overload, rejecting nospam_s
haw.ca
May 7 07:18:21 squid squid[2741]: dnsSubmit: queue overload,
rejecting mailer1.
parl.gc.ca
May 7 07:18:23 squid squid[2741]: dnsSubmit: queue overload, rejecting mail.smi
enkconsulting.com
May 7 07:18:23 squid squid[2741]: dnsSubmit: queue overload, rejecting mx3.regi
omakelaardij.nl
May 7 07:18:23 squid squid[2741]: dnsSubmit: queue overload, rejecting mx3.mail
.national-net.com
May 7 07:18:23 squid squid[2741]: dnsSubmit: queue overload, rejecting mymail.l
eakeandersson.com
May 7 07:18:23 squid squid[2741]: dnsSubmit: queue overload,
rejecting mail.eur
o.net
May 7 07:18:23 squid squid[2741]: dnsSubmit: queue overload,
rejecting dasbeisl
.at
May 7 07:18:23 squid squid[2741]: dnsSubmit: queue overload, rejecting wmail.ha
naro.com
May 7 07:18:24 squid squid[2741]: dnsSubmit: queue overload, rejecting mail.you
.com
May 7 07:18:24 squid squid[2741]: dnsSubmit: queue overload, rejecting mx2.meta
-spinner.com
May 7 07:18:24 squid squid[2741]: dnsSubmit: queue overload,
rejecting mail.uni
te-us.nl
May 7 07:18:24 squid squid[2741]: dnsSubmit: queue overload, rejecting mail.jnb
.ch
May 7 07:18:25 squid squid[2741]: dnsSubmit: queue overload,
rejecting gerrymcc
arthy.com
May 7 07:18:25 squid squid[2741]: dnsSubmit: queue overload, rejecting rmail-al
t1.lycosmail.lycos.com
May 7 07:18:25 squid squid[2741]: dnsSubmit: queue overload,
rejecting backup-m
x.mhs.ch
May 7 07:18:25 squid squid[2741]: dnsSubmit: queue overload, rejecting mail.eco
fer.ch
May 7 07:18:25 squid squid[2741]: dnsSubmit: queue overload, rejecting fairisaa
c.com.s6a2.psmtp.com

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