Hallo,
Dürfen mehrere aufeinanderfolgende Punkte in der email-Adresse vorkommen?
die einfache Antwort auf diese Frage lautet: ja.
siehe RFC 2822:
addr-spec = local-part "@" domain
local-part = dot-atom / quoted-string / obs-local-part
in quoted-string sind mehrere aufeinanderfolgende Punkte erlaubt.
dazu zitiere ich http://www.dns.net/dnsrd/rfc/, DNS related RFCs:
<zitat>
RFC 3696 (Informational)
Application Techniques for Checking and Transformation of Names by J. Klensin
Summarises the syntax of valid DNS names, email addresses, and URLs, so
that programmers can correctly apply local checking of input. Right now,
many applications refuse to accept perfectly valid domain names, email
addresses or URLs because of incorrect assumptions about their syntax.
Should be read by overzealous coders everywhere, but that's probably a
forlorn hope.
</zitat>
wobei mir insbesondere der letzte Satz gefällt.
Und hier noch ein nettes Zitat aus RFC 3696:
<zitat>
The local part may appear using the quoting conventions described
below. The quoted forms are rarely used in practice, but are
required for some legitimate purposes. Hence, they should not be
rejected in filtering routines but, should instead be passed to the
email system for evaluation by the destination host.
</zitat>
Freundliche Grüße
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