svn+ssh over nonstandard port fails to connect

[Chad Perrin]

I'm attempting to connect to a Subversion repository via SSH using a
nonstandard port to check out the repository.  The names and numbers in
the following have been changed to protect the guilty:

  svn co svn+ssh://user@123.45.678.90:1234/usr/home/svn-repos/project project

The result I get is as follows:

  ssh: 123.45.678.90:1234: hostname nor servname provided, or not known
  svn: Connection closed unexpectedly

Am I having a brainless moment here?  What am I missing?

-- 
CCD CopyWrite Chad Perrin [ http://ccd.apotheon.org ]
print substr("Just another Perl hacker", 0, -2);