Is it possible to create an SSH tunnel over http-proxy when https access is denied?

I had such configuration in .ssh\config

Host home
User root
Hostname *my-home-pc-with-ssh-access-allowed*
Port 8090
ProxyCommand corkscrew db-isa-01 8080 %h %p ~/.ssh/.corkscrew-db-isa-auth
IdentityFile ~/.ssh/id_rsa

Where db-isa-01 is my corporate proxy server. Today the admins blocked all https access and allowed it only for few servers on the white list.

I used this command to create a tunnel:

ssh -D 7070 -o 'GatewayPorts yes' -A -q -g -t  root@home

and now it doesn't work. As I can understand, that's because our proxy denies all https connections

Proxy could not open connnection to ***:  Proxy Error ( The specified
Secure Sockets Layer (SSL) port is not allowed. Forefront TMG is not configured to 
allow SSL requests from this port. Most Web browsers use port 443 for SSL requests.  )

P.S. I use Windows 7, and corscskrew with cygwin, so Linux solutions not suitable for me.