Can't specify username with cvs-rsh

[Jim Babcock]

On a shared webhost, my username is "address@hidden" and
the hostname is "jimrandomh.org". With ssh, I can log in fine with
"ssh -l 'address@hidden' jimrandomh.org". However, I can't
find a way to get CVS to pass the correct options. If I use
  export CVS_RSH=ssh
  cvs -d :ext:address@hidden@jimrandomh.org:/cvs init
Then it misparses this as user:jbabcock,
host:address@hidden If I use
  export address@hidden
  cvs -d :ext:jimrandomh.org:/cvs init
then it just ignores the USER environment variable. There doesn't
seem to be any option to specify the username separately (like ssh's
-l).

So, how do I use CVS if my username contains an @ character?