Mi cabecera es:
#include <18F2550.h>
#fuses HSPLL,PROTECT,NOLVP,NODEBUG,USBDIV,PLL1,CPUDIV1,VREGEN,NOPBADEN,BROWNOUT,BORV28,CPB,NOWDT
#use delay(clock=48000000)
#use fast_io(A)
#use fast_io(B)
#use fast_io(C)
#use rs232(UART, BAUD=9600, XMIT=PIN_C6, RCV=PIN_C7, PARITY=N, BITS=8, stream=SIM300)
el error podria estar ahi??