Error with Struct Building

[cmancuso]

After reading over several forums and many posts, I created a custom union type struct for bitwise operations. I followed the p18f452.h header style for the format of the structure. If I just compile the files without invoking the actual variable in code, the code compiles fine. If I go to use the variable I get the error of

MPLINK 4.22, Linker
Copyright (c) 2008 Microchip Technology Inc.
Error - could not find definition of symbol 'CMXCONTROL' in file './cmx.o'.
Errors : 1

A copy of my code snippet is provided below.

//Bit Control of the CMX's Control Register
extern volatile near unsigned char       CMXCONTROL;
extern volatile near union {
  struct {
    unsigned PLLBW:2;
    unsigned LEVRES:2;
    unsigned DARA:1;
    unsigned HILON:1;
    unsigned CKDIV:2;
  };
  struct {
    unsigned PLLBWLOW:1;
    unsigned PLLBWHIGH:1;
    unsigned LEVRESLOW:1;
    unsigned LEVRESHIGH:1;
    unsigned DARA:1;
    unsigned HILON:1;
    unsigned CKDIVLOW:1;
    unsigned CKDIVHIGH:1;
  };  
  struct {
    unsigned PLLBW1:1;
    unsigned PLLBW2:1;
    unsigned LEVRES1:1;
    unsigned LEVRES2:1;
    unsigned DARA:1;
    unsigned HILON:1;
    unsigned CKDIV1:1;
    unsigned CKDIV2:1;
  };  
} CMXCONTROLbits;

void TransmitTQB(unsigned char * pointer)
{
    CMXCONTROL = 0x00;
    CMXCONTROLbits.PLLBW1 = 0;
    
	while(1);
}

Anyone know how to fix this error so I can invoke this way of accessing a variable?