sudo apt-get install возвращает ошибку 404, но ping возвращает пакеты. Это проблема с моими сетевыми конфигурациями?

Я пытаюсь установить openjdk на Ubuntu 11.04 VM на Mac. Тем не менее, я столкнулся с 404 ошибками в командной строке, которые я не могу диагностировать.

sudo apt-get install openjdk-6-jre-headless
...
Err http://ph.archive.ubuntu.com/ubuntu/ natty-updates/main openjdk-6-jre-lib all 6b22-1.10.2-0ubuntu1~11.04.1
404  Not Found [IP: 10.16.3.143 8080]
Err http://ph.archive.ubuntu.com/ubuntu/ natty-updates/main tzdata-java all 2011g-0ubuntu0.11.04
404  Not Found [IP: 10.16.3.143 8080]
Err http://security.ubuntu.com/ubuntu/ natty-security/main openjdk-6-jre-lib all 6b22-1.10.2-0ubuntu1~11.04.1
404  Not Found [IP: 10.16.3.141 8080]
Err http://security.ubuntu.com/ubuntu/ natty-security/main openjdk-6-jre-headless i386 6b22-1.10.2-0ubuntu1~11.04.1
404  Not Found [IP: 10.16.3.141 8080]
Err http://security.ubuntu.com/ubuntu/ natty-security/main icedtea-6-jre-cacao i386 6b22-1.10.2-0ubuntu1~11.04.1
404  Not Found [IP: 10.16.3.141 8080]
Err http://security.ubuntu.com/ubuntu/ natty-security/main icedtea-6-jre-jamvm i386 6b22-1.10.2-0ubuntu1~11.04.1
...

Но если я ping

ping 10.16.3.141
PING 10.16.3.141 (10.16.3.141) 56(84) bytes of data.
64 bytes from 10.16.3.141: icmp_req=1 ttl=63 time=1.55 ms
64 bytes from 10.16.3.141: icmp_req=2 ttl=63 time=3.22 ms
64 bytes from 10.16.3.141: icmp_req=3 ttl=63 time=4.00 ms
64 bytes from 10.16.3.141: icmp_req=4 ttl=63 time=174 ms
64 bytes from 10.16.3.141: icmp_req=6 ttl=63 time=4.16 ms
64 bytes from 10.16.3.141: icmp_req=7 ttl=63 time=2.19 ms
64 bytes from 10.16.3.141: icmp_req=8 ttl=63 time=4.98 ms
64 bytes from 10.16.3.141: icmp_req=9 ttl=63 time=3.81 ms
64 bytes from 10.16.3.141: icmp_req=10 ttl=63 time=6.09 ms
64 bytes from 10.16.3.141: icmp_req=11 ttl=63 time=3.89 ms
64 bytes from 10.16.3.141: icmp_req=12 ttl=63 time=3.86 ms
64 bytes from 10.16.3.141: icmp_req=13 ttl=63 time=0.009 ms
64 bytes from 10.16.3.141: icmp_req=14 ttl=63 time=3.99 ms
^C
--- 10.16.3.141 ping statistics ---
14 packets transmitted, 13 received, 7% packet loss, time 13047ms
rtt min/avg/max/mdev = 0.009/16.610/174.132/45.496 ms

Любые идеи? Это проблема моей сети?