Yazsoft today announced the availability of Speed Download 4.1, an important update to the company’s download manager for Mac OS X. Changes in version 4.1 include: optimized performance for Mac OS X 10.4.7; added full support for WEBDAV and WEBDAV-SSL servers; improvements to the file sharing feature set; and many more tweaks and bug fixes. Speed Download is priced at US$25. A free 21-day trial is also available.