URL for NWBC for HTML with multiple backend

Hello

We use NWBC for HTML and MIM.

We have a webserver with an Apache running that connects to multiple SAP-ECC backend systems.

We want to use only one domain,  http://www.mydomain.com/ to connect to the webserver, and change the url to point to the backends.

http://www.mydomain.com/dir1/       --->      http://localhost1:8000/nwbc

http://www.mydomain.com/dir2/       --->      http://localhost2:8000/nwbc

In both backend systems we have created an alias in SICF for nwbc:

/dir1  -> /default_host/sap/bc/nwbc

/dir2  -> /default_host/sap/bc/nwbc

In Apache we wrote:

ServerName www.mydomain.com

ProxyPass                 /dir1     http://localhost1:8000/

ProxyPassReverse     /dir1     http://localhost1:8000/

ProxyPass                 /dir2     http://localhost2:8000/

ProxyPassReverse     /dir2     http://localhost2:8000/

-> It does not work, the problem seems to be that SAP publishes pages with internal links to "/sap/public/bc/...."  and the final URL is like http://www.mydomain.com/sap/public/bc...", so the proxypass fails.

How can we solve this problem?

Is it possible to specify in each SAP-ECC backend that links should be created as:

"/dir1/sap/public/bc/...." 

"/dir2/sap/public/bc/...." 

We've tried to create an alias in SICF for /sap directory but it does not work.

Any help, please?