As copy paste user I never realized the difference between that address :us.archive.ubuntu.com

and

old-releases.ubuntu.com

Yes, old-release hold old version ubuntu that not supported any longer. I see that when I need to install php5-curl on Maverick and I get 404 message.

Change sources.list entry from us.archive.ubuntu.com to old-releases.ubuntu.com give me php5-curl 🙂

# apt-get install php5-curl
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following packages were automatically installed and are no longer required:
libfreeradius2 freeradius-common freeradius-utils libperl5.10
Use ‘apt-get autoremove’ to remove them.
The following NEW packages will be installed:
php5-curl
0 upgraded, 1 newly installed, 0 to remove and 125 not upgraded.
Need to get 25.5kB of archives.
After this operation, 127kB of additional disk space will be used.
Install these packages without verification [y/N]? y

Check install :

# dpkg -l | grep curl
ii  libcurl3                        7.21.0-1ubuntu1                   Multi-protocol file transfer library (OpenSSL)
ii  libcurl3-gnutls                 7.21.0-1ubuntu1                   Multi-protocol file transfer library (GnuTLS)
ii  php5-curl                       5.2.10.dfsg.1-2ubuntu6            CURL module for php5

don’t forget to restart apache to get into business.