Hello
If you are using a Palm Treo 680, the analog dual sim adapter type 3 from www.2-phones-in-1.com is the best choice.
See the adapter here.
http://www.2-phones-in-1.com/english/products/dual_sim_holder_adapter_type_3.htm
No need to cut your simcards .
Please also see here:
http://metaviewsoft.de/wordpress/?p=47
This user describes in details how he uses type 3 analog from 2-phones-in-1.com with his Treo 680