Pushing certificates with Airwatch to authenticate on Exchange and corporate websites

Hello,

We are using Airwatch for ours iPad.
Users register to Airwatch with their MS Active Directory account. Airwatch pushes a X509 Certificate (based on the user account and issued by our MS PKI) on the device.

We have two use cases :
- users access email via MS Exchange Activ Sync : authentication is done using MS Active Directory user/password
- users access extranet web applications : authentication is done by CA SiteMinder using the iPad X509 certificate

If the AD password expires, users don't have the possibility to change it with the iPad. They need to connect to corporate network on the LAN with their desktop.

I have several questions

1) Can we use the certificate to authenticate on Exchange?
What we need to do on Exchange, on Airwatch (if necessary) and on the iPad?

2) Can we use the fisrt certificate pushed by Airwatch or we need to issue another one for Exchange with specific caracteristics?

Thanks for your help
Regards
Laurent