use AppleScript version "2.3"
use scripting additions
use framework "Foundation"
on doIt()
set theSource to "<html><body><H1>It can be done</H1><hr><p><a href="" href="http://www.macosxautomation.com/applescript/apps/\" class="">http://www.macosxautomation.com/applescript/apps/\">Good stuff here</a></body></html>"
set theSource to current application's NSString's stringWithString:theSource
set theData to theSource's dataUsingEncoding:(current application's NSUTF8StringEncoding)
set theStyledText to current application's NSAttributedString's alloc()'s initWithHTML:theData documentAttributes:(missing value)
set mailShare to current application's NSSharingService's sharingServiceNamed:(current application's NSSharingServiceNameComposeEmail)
mailShare's setSubject:"I wish"
mailShare's performWithItems:{theStyledText}
end doIt