dependency not satisfied (same PPA)

Hi, I have problem to build some packages on Launchpad, eg. [1]. The build fails with

"""
The following packages have unmet dependencies:
 sbuild-build-depends-grass-daily-dummy : Depends: libgdal-dev
                                          Depends: libgeos-dev but it is not going to be installed
"""

Even both packages (libgdal-dev and libgeos-dev) are available in Ubuntu Precise and moreover in the same PPA where I have built this package. This error seems to be related to the fact that I have these packages in the same PPA [2], any idea why? Thanks a lot in advance! Martin

[1] https://launchpadlibrarian.net/249829710/buildlog_ubuntu-precise-amd64.grass-daily_7.1.svn-4-r68124~ubuntu12.04.1_BUILDING.txt.gz
[2] https://launchpad.net/~landa-martin/+archive/ubuntu/gislab-gismentors/+packages