libraries for 16 bit PICs

Hi

I have been using a 16F877A and the serial libraries supplied with 
the compiler to communicate with my PC.  I need to change the 16F877 
PIC to a 18F4xx pic.  I have not yet been able to find a serial 
library for JAL which support the newer 16 bit PICs.

Does anybody have these libraries already or do I have to make my 
own?

Thanks
Nick