(12.04) unable to install libxrender-dev: unresolvable dependencies

[lookabout]

hello, it appears the latest libxrender-dev package is one version behind the latest libxrender1 package.

after some googling this is the info i have:

apt-cache showpkg libxrender1
Package: libxrender1
Versions: 
1:0.9.6+git20100705.d3d20437-0ubuntu0sarvatt~lucid (/var/lib/dpkg/status)
 Description Language: 
                 File: /var/lib/apt/lists/ca.archive.ubuntu.com_ubuntu_dists_precise_main_binary-amd64_Packages
                  MD5: 1529276fe319e97fa1c4f85128ed50b8

apt-cache showpkg libxrender-dev
Package: libxrender-dev
Versions: 
1:0.9.6-2ubuntu0.1 (/var/lib/apt/lists/ca.archive.ubuntu.com_ubuntu_dists_precise-security_main_binary-amd64_Packages) (/var/lib/apt/lists/ca.archive.ubuntu.com_ubuntu_dists_precise-updates_main_binary-amd64_Packages)
 Description Language: 
                 File: /var/lib/apt/lists/ca.archive.ubuntu.com_ubuntu_dists_precise_main_binary-amd64_Packages
                  MD5: 90cef1620b30f07a5c21955d91855734

a search at http://packages.ubuntu.com/search?ke...libxrender-dev confirms 1:0.9.6-2ubuntu0.1 is the latest available libxrender-dev package.

attempting to install libxrender-dev through synaptic fails with "the following packages have unresolvable dependencies"

libxrender-dev:
  Depends: libxrender1 (=1:0.9.6-2ubuntu0.1) but 1:0.9.6+git20100705.d3d20437-0ubuntu0sarvatt~lucid is to be installed

is there a reason why the repositories have this mismatch?
what is the usual way to progress, should i try to compile the libxrender-dev from source?
some google results suggested forcing the libxrender1 version down a level, but i'm afraid to do that considering it has 195 packages depending on it and this latest version seems to be legitimate.
does everyone on 12.04 have this problem or is there something i did?

thanks for your help!

edit: according to http://packages.ubuntu.com/search?keywords=libxrender1 the latest official version of libxrender1 is 1:0.9.6-2ubuntu0.1.

i issued the apt-cache showpkg libxrender1 command after searching google for a way to find the source of an installed package.

why does this command tell me the package comes from the ca.archive.ubuntu.com mirror in the precise main category but the ubuntu package search doesn't show this package?

as far as i know i got the package from the automatic update tool.

edit2:

grep libxrender1 /var/lib/apt/lists/* | grep "Filename:"

shows no mention of a 1:0.9.6+git20100705.d3d20437-0ubuntu0sarvatt~lucid version of the package.

[lookabout]

after reading more about the chain of trust in Ubuntu package deployment, i found i had "xorg crack pushers" under my trusted software providers. i'm guessing the error was that i had added a repository at some point, gotten a package update, then removed that repository. at that point trying to update another package to the version supported by that repository failed.

i was unable to fix the problem with ppa-purge, so i did the following steps

dpkg -l | grep <version tag>

for version tag in this case i used "sarvatt". for each item in the list i ran

apt-cache showpkg <package>

which showed the currently installed version and the previous official version. in a new file i added a command

apt-get install <package>=<version>

for each file where version was the previous official version. then i shut down x windows and ran this script. everything seems to be working fine and i was able to install libxrender-dev without a problem.