Comment #12 on issue 979 by pekka.klarck: Imporing Python library implemented as directory using physical path or when it is in the execution directory fails
http://code.google.com/p/robotframework/issues/detail?id=979
Thanks for kind words! Especially hearing that you are replacing QTP and QC with Selenium and Robot Framework, and doing that for a big client, makes me happy. =)
Were you able to workaround the problem? I believe moving the library under src directory or somewhere else so that it isn't in your working directory is the easiest solution.