VPN Client problem with dial-up & Mac OS X

[ppilote]

Client version 4.7.00.0510 on Mac OS X (10.4.2). Getting the following error message when trying to establish VPN connection "VPN subsystem unavailable". No problem when using the same Mac with the LAN interface. I know Macs r not the most popular subject here but if anyone can help... Thanks.

[thomas.chen]

VPN Concentrator release 4.1.7 supports the Outlook/Exchange (MAPI) Proxy for Microsoft Exchange e-mail, with specific versions of Outlook and Exchange. These are supported:

Exchange 2000

Exchange 2003

Outlook 2000

Outlook XP

These are not supported in the current version:

Outlook 2003 is not supported with any version of Exchange Server, but it will be supported in future releases.

Exchange 5.5.