Help Sending SMS to email address not working

On my previous (cheap, basic) phones, I could send an SMS message to any email address. If I addressed it to an email address instead of a phone number, it just did it automatically.

I now have a Galaxy Ace, and it doesn't seem to do this. When I attempt it, it switches to creating an MMS message instead, and gets stuck when attempting to send it.

I do not have a data plan. I'm with Virgin Mobile (Canada) on a basic pre-paid plan for calling and texting (SMS). It's the same plan I was on with the previous (non-smart) phones.

I've tried using both the built-in Messaging app and Handcent with the same results.

Any ideas? How can I get it to just send the message and let Virgin deal with the email address?

I'm new to android, so I'd appreciate any ideas or pointers. Thanks!