Multimedia macro doesn't work with SWF files that have 'attachment' word in the name

For some reason, when using the multimedia macro with SWF files that have 'attachment' word in the name, the macro simply don't render in the page.

Steps to reproduce

1) Download the attached swf files

2) Attach them to a page

3) Insert a multimedia macro and save the page with those two files.

The macro won't render for files with the 'attachment' word in the name.