Client certificates not passing from IISPROXY to ICM

Issue - 1: While posting https requests, the client certificates from

IISPROXY (Running on IIS DMZ server) are not being received by SAP ICM.

Issue / Scenario - 2: Customer is sending XML files using http(s) post

using digital certificates (X 509) to the DMZ – IIS Server. The

IISproxy (installed on the IIS server) routes the request accordingly

to the WebAS server (Prefix /bw). We have imported client certificates to

SAPGENPSE. Now, SAP ICM receives the IIS client certificate and logins

with a user id mapped to the IIS client certificate.

What is happening to the original client certificate coming along with

the request. Why is ICM receiving the IISproxy client certificate and

not the original client certificate?