svn+ssh tunneling help

I access a subversion development repository on an OpenBSD server remotely.

Under Windows I execute a batch file

that runs:

 plink -L 3690:localhost:3690 -i id_rsa.ppk -P 22222 -N svntun@mycomp.com

And then I can checkout with

svn co svn://localhost/ .

I have managed to get this working under Linux using ssh as

ssh -L 3690:localhost:3690 -p 22222 -N svntun@mycomp.com

I have tried all combinations of custom commands in my ~/.subversion/config

[tunnels]
# ssh = $SVN_SSH ssh -p 22222 -i /home/root/.ssh/id_rsa
pico = ssh -p 22222 -N svntun
# pico = ssh -L 3690:localhost:3690 -p 22222 -N svntun@mycomp.com
# pico = ssh -v -i /root/.ssh/id_rsa -p 22222 -l svntun
plink = plink -v -i /root/.ssh/id_rsa.ppk -P 22222 -l svntun

to try to get something like
svn co svn+pico://mycomp.com/ . working

with no success.

A web search offered

svn co svn+ssh://svntun@mycomp.com:22222/ .

which seems reasonable but results in syntax errors

Is there some way I can use the svn ssh tunnel to my repositories
without having to
run the tunnel as a separate process ?

-- 
Dave Lynch 					  	    DLA Systems
Software Development:  				         Embedded Linux
717.627.3770 	       dhlii_at_dlasys.net 	  http://www.dlasys.net
fax: 1.253.369.9244 			           Cell: 1.717.587.7774
Over 25 years' experience in platforms, languages, and technologies too numerous to list.
"Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction."
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