Ok, slowly solving my own problems.
It seems that the directory for the sources is what I need. However, linuxmce does not include the sources anymore, [http://smart-home-blog.com/archives/1155]
I need to use the original ones from the vdr-project, which I downloaded here: [tp://ftp.cadsoft.de/]
However, now I got Problems with make. Running just 'make' on VDR tells me that fontconfig cannot be found, however apt tells me its version 2.4.2 which should be fine. Any ideas?
Sorry, if all this seems trivial, but it is quite an insight for me. Maybe for other newbies as well.
I can provide you with all sources you need to compile things against the vdr version we use in lmce 0710.
Im not sure I can upload them today. Have to find a place other than my private server.