ImageMagick 6.7.8-9 2013-03-10 Q16 http://www.imagemagick.org
It was installed from the Fedora 19 repositories. I also compiled 6.8.7-5 from source to check whether it was a fixed bug. The issue persisted in 6.8.7-5.
Command Issued:
convert -interlace line *.jpg out.gif
Test Images:



Output:
