Validate Email Flash Form

Hi All
cfform validation is driving me nuts.
I have a simple form with a submit button and an input text field.
I need to validate the form field for an "email" with an apostrophe in it.

If I use a html form the cf validation works correctly, but as soon as I add format="flash" the validation fails.

Can you tell me why this is giving an error.

Some sample code
<cfform method="get" name="myform" format="flash">
<cfinput type="submit" name="submit" value="submit" />
<cfinput type="text" name="email" label="Email" validate="email" validateat="onsubmit" required="yes" message="Invalid Email">
</cfform>

Ken