[TYPO3-english] simple mail not working with default mail settings

[Domi]

Hello,

I try with the simple mailform of TYPO3 4.7 to create mailforms. First 
it seemed that everything works as expected.

BUT: anytime someone tries to type into an input field with a field name 
"email" and the user chooses a yahoo or gmail address, following error 
gets displayed:

Expected response code 250 but got code "550", with message "550 You are 
not allowed to use the domain gmail.com as a sender domain. "

"email" are the default fields from TYPO3 core if I start with the 
element. And now after hours of testing its actually a huge bug, that 
this email field needs to get renamed... Well sometimes I don't 
understand TYPO3...

The second weird thing: Required is available for all element types, but 
not for checkboxes. So how many time do somebody needs to check that he 
understand TermsAndConditions or something else...I think it would 
really make sense that a more serious mailform would ship in with TYPO3 
in the core.

Cheers Dominic