cannot install libgl1-mesa-dev via apt-get

[Capricorny]

When I tried to install it, I got the following error:

root@Microknoppix:/wine-git# apt-get install libgl1-mesa-dev
Reading package lists... Done
Building dependency tree 
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
 
The following packages have unmet dependencies:
libgl1-mesa-dev : Depends: libgl1-mesa-glx (= 7.7.1-4) but 7.9+repack-2 is to be installed
E: Broken packages

I have no clues why it happens.

Did you really read the error message?

 
The following packages have unmet dependencies:
libgl1-mesa-dev : Depends: libgl1-mesa-glx (= 7.7.1-4) but 7.9+repack-2 is to be installed
E: Broken packages

Which tells about a version conflict. You may have to look up repositories to get compatible package versions, and in some cases, you're simply stuck. You should always check actual versions before installing - which is why tools like synaptic may be handy.