[Dovecot] using complete email address as username

[WJCarpenter]

I've been poking around the dovecot wiki, and this idea looks
plausible.  I'm just double-checking with the assembled experts to see
if there is some "gotcha" that will happen to me down the road.

I have in mind a deployment of dovecot which will use serve several
unrelated domains.  My plan is to use the complete email address of
the users as the unique userid.  So, for example, a user with email
address <foo at example.COM> is unrelated to a user with email address
<foo at example.NET>.  The "home" directories of such users will look
something like:

  /some/path/foo at example.com/
  /some/path/foo at example.net/

I do also plan to use ACLs for some things, so there could be ACL
entries of the form:

  user:foo at example.com ...

I will probably be using the quota plugin for individual users right
away and group quotas later when that's officially available.

So, is all this likely to work or will it collapse in a miasma of
unmet expectations?

Thanks in advance for any comments!