Bypass of JUCE check with "FROM:" with relay option 2 selected.
In version 3 of GMS Mail, using relay option 2 (i.e. relay for a set of listed
domains), the “From:<>” clause is interpreted (incorrectly) as a local domain
allowing email through the server.
Reported by: NTBugtraq
Don’t use this option – use default anti-relay (option 1).
Upgrade to version 4 of GMS Mail.