Unfortunately, the SecureClient from CheckPoint doesn’t support 64bit environments. Nearly every Mac you can buy today supports 64bit as default. Brings a lot of benefits, but thats a whole other topic. So, the CheckPoint client currently only works in 32bit Snow Leopards.

There is two ways to achieve that.

Default boot into 32bit. This is described in the Knowledge Base entry on the Apple page here: http://support.apple.com/kb/HT3773

Second: Press 3 + 2 while booting up the system. Guess which key combination you have to press if you want a 64 bit system!?

Hope that helps.