[Evolution] Customised alarm - no email

[Dougie McGilvray <dmcgilvray f2s com>]

Hi, I'm trying to sort my life out with evolution. But I can't seem to 
set an email reminder for appointments. Here's my process:

Create an appointment/meeting.
Enable alarm.
Click customiase
Add an alarm.
Now the options for the alarm are: pop up alert, play a sound, run a 
program, or email - but email is blanked out and unselectable.

I have my email accounts set up in evo, and have set a default account. 
What am I missing?

Cheers