Seamless, color balanced mosaics of aerial RGB photos with Open Source

I'm looking for an open source tool/workflow (even a command line one) to obtain what it is advertised in programs like

http://www.inpho.de/index.php?seite=index_orthovista

http://www.orthomapper.com/color_balance_example.html

http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//009t000001v8000000

I already tested OSSIM and GRASS, for instance

http://trac.osgeo.org/ossim/wiki/histogram_operations

http://grass.osgeo.org/grass64/manuals/i.image.mosaic.html

but results are not as expected. I also had no luck with

http://www.lizardtech.com/products/geoexpress/

that is the only close source that I was able to test thanks to a trial.

Maybe it depends from my input data, so a small working sample dataset would be highly appreciated.

By the way, does Orfeo do something like that?

Thanks in advance

PS I'm open to use even a non GIS software