[Joeriginal]

If you want QMail to invoke automatically every time you tap a 'mailto:' link in Pocket IE, you should change some things in registry (as you may guess!)

\HKCR\mailto\Shell\Open\Command - rename Default to Default_old. Create new string value Default, then set it to "\full path\to the program\QMail\q3u.exe" -s "%1" (do not forget quotation marks!)

Use the next tweak if you do not want Inbox to start in the background every time you put your device in the cradle for syncing.

\HKLM\SOFTWARE\Microsoft\Shell\Event\Dock\Inbox - rename command to command_old.

I dont know if this will help you or even work, as I havent tried it, but give it shot if you want. Not my formula, found it on the web.