Upgrade to version 1.6 or higher, as it has been reported to fix this vulnerability. An upgrade is required as there are no known workarounds.
Vendor URL: http://www.mailenable.com/
Vendor Specific News/Changelog Entry: http://www.mailenable.com/professionalhistory.asp
Related OSVDB ID: 17981
Related OSVDB ID: 17982
Related OSVDB ID: 17984