Just test your interrupt flag bits in the int handler. These tell you which source generated the interrupt condition.
Code:
ORG 0x4

 ; save state if needed here

ISR
  btfss INTCON,T0IF ; if TMR0 interrupt, handle it 
  goto RB_INT       ; else skip to RB_INT

T0_INT
  ; CODE 2......(ON TOIE)
  bcf   INTCON,T0IF ; clear TMR0 int flag, and run handler

  ; insert your timer0 int handler here

RB_INT
  ; CODE 1..... (ON RBIE)
  bcf   INTCON,RBIF ; clear RB int flag, and run handler

  ; insert your RB int handler here

ISR_EXIT
  ; restore state if needed here

  retfie