PIC18F45J50 UART remappable problem
Set Analog pins as digital...  ADCON1=0X0F;


Setting analog port pins to digital is done via the ANCONx registers, not ADCONx.

To enable digital input on RP0 you must set bit PCFG0 in register ANCON0. 


  BTW.. RP0 and RP1 represent pin 19 and 20 resp.. which is RB0 and RB1
  normally..


Pins 19 and 20 on the PIC18F45J50 are RA0 (AN0) and RA1 (AN1).