TMG2F5 Series: BIG-IP LTM as the Lync Reverse Proxy

Hello, Any documentation I found about revers proxy publishing with BIG IP says: "The certificate you select here MUST match the certificate used in your Lync web services configuration"- (I might need to search for other documentation) while TMG was able to publish the external web sites using a different certificate configured on the TMG listener. Could you confirm that this is not a limitation in the BIG IP and publish the Lync web services through reverse proxy with a publicly trusted certificate? (On the Lync servers internally issued certificates are in use.) Thank you for your help in advance! BR, Ferenc