Question on 0.0.0.0.in-addr.arpa queries

2 msg	bind 9.5 http
10 msg	couldn't open pid file '/var/run/named.pid': Pe...
4 msg	Re: BIND 9.5.0a7 is now available.

Question on 0.0.0.0.in-addr.arpa queries
\ Fr34k (14 Nov 2007)
. \ Mark Andrews (14 Nov 2007)

2 msg	Troubles with DNS
1 msg	bind 9.5 DLZ --- SOA enteries in record ?
2 msg	check-names warning?
6 msg	Glue records cached, when they should be coming...
1 msg	GSS TSIG configuration
3 msg	Convert MSDNS to bind
6 msg	switching query-source address on timeout and e...
2 msg	rndc + key + control
3 msg	Sv: Re: BIND forward to Windows DNS
4 msg	BIND forward to Windows DNS
2 msg	clients-per-query
2 msg	Re: [Re: NSEC3 support for BIND]
5 msg	bind generating db-* files
2 msg	error when rebuilding bind binaries ( undefined...
1 msg	Godaddy.com + DNS glue records
3 msg	BIND threads

Subject:	Question on 0.0.0.0.in-addr.arpa queries
Group:	Bind-users
From:	Fr34k
Date:	14 Nov 2007

Hi All,

I see the following from many customer devices when snooping DNS queries:

a.client.net -> a.dnsserver.com DNS C 0.0.0.0.in-addr.arpa. Internet PTR ?
a.dnsserver.com -> a.client.net DNS R Error: 3(Name Error)
a.client.net -> a.dnsserver.com DNS C 0.0.0.0.in-addr.arpa. Internet PTR ?
a.dnsserver.com -> a.client.net DNS R Error: 3(Name Error)
a.client.net -> a.dnsserver.com DNS C 0.0.0.0.in-addr.arpa. Internet PTR ?
a.dnsserver.com -> a.client.net DNS R Error: 3(Name Error)
a.client.net -> a.dnsserver.com DNS C 0.0.0.0.in-addr.arpa. Internet PTR ?
a.dnsserver.com -> a.client.net DNS R Error: 3(Name Error)

Thoughts?
I am seeing this on Solaris with Bind9.4.1-P1

Thank you -- Chris