Extracting attachments, filenames with spaces

I store my extracted attachments in a web-accessible directory and can access
the files in my browser. If the attachment was MSWord, my mailcap specifies a
call to a script that converts MSWord files to HTML. Everything works fine
except when the filename contains spaces. So I had the following idea. In the
Save/ Extract attachments (under More... in exmh 2.7.2), change spaces in
filenames to underscores? This could be an option (Preferences... MIME) besides 
the option of specifying the save location.

-- 
rick baartman