com nameserver caching

[rh]

hi all,
if you lookup www.1and1.com, most queries come back with:
217.160.226.203.
but i started noticing that a couple of my dns servers were returning
a wrong ip: 217.160.232.1

after some digging, i noticed that the com namesavers actually have
this RR cached like so:
[~]$ dig +norec @h.GTLD-SERVERS.NET www.1and1.com

; <<>> DiG 9.2.4 <<>> +norec @h.GTLD-SERVERS.NET www.1and1.com
; (1 server found)
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29492
;; flags: qr; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2

;; QUESTION SECTION:
;www.1and1.com.                 IN      A

;; ANSWER SECTION:
www.1and1.com.          172800  IN      A       217.160.232.1

;; AUTHORITY SECTION:
1and1.com.              172800  IN      NS      ns27.1and1.com.
1and1.com.              172800  IN      NS      ns28.1and1.com.

;; ADDITIONAL SECTION:
ns27.1and1.com.         172800  IN      A       74.208.2.3
ns28.1and1.com.         172800  IN      A       74.208.3.3

---------------------------------------------------------------

is this normal? i don't see any other RR's for major companies in
these nameservers. i assume because of this the iterative query stops
at this point and returns this bad ip without going further to the
authoritative nameservers for 1and1.com.

opinions?

thanks