Just an FYI that CaptureOne 4.5.1 is available for download from Phase One's site.
Here is a brief excerpt from the read me:
"New Camera Support
EOS 50D (Raw files only)
EOS 5D Mark II (preliminary, Raw files only)
Solved issues
Improved stability
Better sharpness when in "Zoom to Fit" mode
Consistency of output when processing multiple recipes
Increased robustness for Chromatic Aberration Analysis
Improved sharpness when applying Lens Distortion and resizing images
License information shown in about box
Support for Pentax K20D Camera using firmware 2.0
Warning when launching on Mac OSX 10.4.x and/or PowerPC
Solved problem causing wrong cursors to be shown.
Sorting by ISO now possible
Crop composition grid enabled for all versions
Solved problem preventing the Preferences from showing
ICC profile file location
Solved issues relating to copy/apply of Styles and LCC and Color Cast
Better Lens tool defaults
Fixed the keyboard shortcuts for selecting tool tabs
"The given key was not present in the dictionary" issue resolved
Automatically starting the importer on auto load cd/dvd/memory card"