Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
You may need to upgrade. We tried your command with ImageMagick 6.2.7-8, the current release, and it worked fine (produced a usable Group4 TIFF image).
