SSH tunnel over http proxy with blocked 443 (SSL)

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.