Rechtsklick auf Dateil > Senden an > E-Mail-Empfänger / right click on a file > send to > email recipient in VISTA

hi,
i use thunderbird portable.
with outlook it was possible to make a right clik on a file and click "send to mail recipient", then outlook opend the mail window with the attached file.

How can i set thunderbird portable as standard mail client and also send files with a rightclick?????

Thanks for your help!
sunshine