Watchguard MUVPN

I do not know much about VPN other than the basics and how to use what has already been set up for me or what I can follow in a straight forward guide.

So my question is:
Can I use another VPN client (other than the muvpn) provided by watchguard in order to access my SOHO 6?

I have a work client VPN using Nortel, and the two are not compatible. And I think it ridiculous to have 2 laptops for the 2 places I need to VPN into.

If I can use my Nortel or something else, can you point me in the right direction?

Thanks!