I am not sure this "smart paging" is 3GPP defined feature or patented idea/concept. But googling found a number of web references.
Smart paging concept would be essential when network operator would like to optimize paging signalling.
As all of us know, paging for an UE is triggered to all the cells/enodebs of TAI(s) where the UE is registered. A tracking area itself may consists of hundreds of eNodeBs , it would be efficient way to page an UE for all the eNodeB.
Some smart mechanism or algorithm should be present in MME so that somewhat paging can be optimized.
I am sharing one of the web reference. It may help you .
http://www.google.co.in/patents/US**********