Problem creating certificate for web client

Hi,

I want to be able to create a test client certificate signed by a test CA and establish a SSL connection and identify the client using this certificate using IIS7 and Firefox on Windows 7, all locally on a development machine. I am deploying my MVC application from VS2010. So far I have done the following:

1. Created the CA using:

makecert -n "CN=mydomain" -r -pe -sv DevCA.pvk DevCA.cer -sr LocalMachine -a sha1 -sky signature -cy authority

2. Create a client certificate signed by DevCA:

makecert -sv testclient.pvk -iv DevCA.pvk -pe -a sha1 -sky Exchange -eku 1.3.6.1.5.5.7.3.1,1.3.6.1.5.5.7.3.2 -n "CN=mydomain" -ic DevCA.cer testclient.cer -ss My -sr LocalMachine

3. Create PFX files of the two certificate:

pvk2pfx.exe -pvk testclient.pvk -spc testclient.cer -pfx testclient.pfx
pvk2pfx.exe -pvk DevCA.pvk -spc DevCA.cer -pfx DevCA.pfx

4. Use certmgr to import DevCA to trusted root certificates

5. In IIS manager:

    a) Added testclient.pfx to 'Server Certificates'
    b) In my site, set SSL Settings to accept SSL
    c) Set HTTPS bingings to use testclient certificate

6. In Firefox I then add DevCA to Authorities tab and testclient to 'Your Certificates', in IE I import CA and client certificates using certmgr.

When I navigate to my application in Firefox using HTTPS I get:

"Connection is untrusted"

In IE I get:

"HTTP Error 403.16 - Forbidden, Your client certificate is either not trusted or is invalid."

If I then add an exception I can establish an SSL connection but within my application I cannot get details of the client certificate using:

HttpClientCertificate cert = this.Request.ClientCertificate;    
if (cert.IsPresent) etc..

Not sure what I'm doing wrong here. Any ideas?

Thanks,

Richard