[Mimedefang] That .com extension

[Joseph Brennan]

An attachment with this name was snagged as an executable by the
example filter_bad_filename routine:

WSJ.com - Cutting Hedge_ Law Firm Grows With Funds.pdf

It must be because of the ".com " in the name.

Why do we not just test the value of lc($ext), rather than pass the
entire entity to filter_bad_filename?  Is there some form of obfuscation
in which the filename could be WSJ.com followed by random text?

Joe Brennan