host and domain with same name

Hello,

anyone has hints/advices about the following problem:

We (GARR-NIS) have registered a new domain under .it with the following records:
	eurolan.it.		604800	NS	ns.iunet.it.
				604800	NS	eurolan.it.
	eurolan.it.		A	192.106.195.1

As you can see one of the servers (a secondary at the moment, may become
the primary in the future) has the same name of the whole domain.
I think this should not be a problem, but querying our server we
do not get information about autoritative servers:
	Query about eurolan.it for record types ANY
	Trying eurolan.it ...
	Query done, 1 answer, authoritative status: no error
	eurolan.it          	432000	IN	A	192.106.195.1

On the contrary, querying the primary server we get the right answer:
	Query about eurolan.it for record types ANY
	Server: ns.iunet.it
	Address: 192.106.1.1
	
	Trying eurolan.it ...
	Query done, 8 answers, authoritative status: no error
	eurolan.it    	14400	IN	SOA	ns.iunet.it postmaster.iunet.it (
			930224	;serial (version)
			28800	;refresh period
			14400	;retry refresh time
			604800	;expiration period
			14400	;default ttl
			)
	eurolan.it          	432000	IN	NS	ns.iunet.it
	eurolan.it          	432000	IN	NS	eurolan.it
	eurolan.it          	172800	IN	A	192.106.195.1
	eurolan.it          	14400	IN	MX	0 eurolan.it
	eurolan.it          	14400	IN	MX	10 relay.iunet.it
	eurolan.it          	14400	IN	MX	20 relay1.iunet.it
	eurolan.it          	14400	IN	MX	50 mcsun.eu.net
	Additional information:
	ns.iunet.it         	604800	IN	A	192.106.1.1
	ns.iunet.it         	463543	IN	A	130.251.1.17
	eurolan.it          	172800	IN	A	192.106.195.1
	relay.iunet.it      	14400	IN	A	192.106.1.2
	relay1.iunet.it     	14400	IN	A	192.106.1.3
	mcsun.eu.net        	94962	IN	A	192.16.202.1

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Antonio_Blasco Bonito                          E-Mail: bonito@localhost
GARR - Network Information Service      c=it;a=garr;p=garr;o=nis;s=bonito
c/o CNUCE - Istituto del CNR                         Tel: +39 (50) 593246
Via S. Maria, 36                                    Telex: 500371 CNUCE I
56126 PISA   Italy                                   Fax: +39 (50) 904052
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