Comment #12 on issue 736 by pekka.klarck: Uncatchable syntax errors should be turned into normal failures when possible
http://code.google.com/p/robotframework/issues/detail?id=736
Also OperatingSystem's process related keyowrds use ConnectionCache and issue 853 reported that Stop Process fails with an uncatchable error. That was fixed in revision 85735c360574 (see comment 6) when ConnecitonCache was changed to use RuntimeError instead of DataError.
