DNS hacked

Looks like Granite Canyon was hacked today. A coworker went to
his web site this morning and noticed it had suddenly become a
porn site. He uses GC for DNS. The evidence:

At 12:00pm today:
H:\>nslookup irvingtech.com
Server: dc201dir01
Address: 10.6.34.92

Non-authoritative answer:
Name:    irvingtech.com
Address:  64.128.184.145

H:\>nslookup www.irvingtech.com
Server: dc201dir01
Address: 10.6.34.92

Non-authoritative answer:
Name:    www.irvingtech.com
Address:  66.34.137.1

Yet at 5pm:
H:\>nslookup irvingtech.com
Server: dc201dir01
Address: 10.6.34.92

Non-authoritative answer:
Name:    irvingtech.com
Address:  64.128.184.145

H:\>nslookup www.irvingtech.com
Server: dc201dir01
Address: 10.6.34.92

Non-authoritative answer:
Name:    irvingtech.com
Address:  64.128.184.145
Aliases:  www.irvingtech.com

Now it's back to normal with no action on his part. Has anyone
heard about any problems over at GC?

George