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?".
We will investigate but in general a status other than 0 means ImageMagick could not complete an operation. The exception you are receiving is a warning that a particular scanline had a problem but overall the image could be read. This command for example,
convert nosuchimage.gif image.png
correctly returns a status of 1 because no part of the image was read.
We'll add a -regard-warnings option to the command line utilities to address the issue you raised. Look for a patch in ImageMagick 6.2.8-6 Beta within a day or two.