: error C141: syntax error near 'reg', expected ')'

I am porting an Arduino program to an 8051 chip to program nrf24le1.
I am getting this error message in the keil Uvision 4 compiler.
..\HAL\FUNCTIONS.H(3): error C141: syntax error near 'reg', expected ')'
and this is what is in the functions,h file:
void nrfInit();
void config();
void configRegister(uint8_t reg, uint8_t value);
void setTADDR(uint8_t *adr);
void writeRegister(uint8_t reg, uint8_t *value, uint8_t len);
void transmitSync(uint8_t *dataout,uint8_t len);
void transferSync(uint8_t *dataout,uint8_t *datain,uint8_t len);
void send(uint8_t *value);
void transmit(const char *string);
void powerUpTx();
void powerUpRx();
uint8_t getStatus();
void flushTx();
void readRegister(uint8_t reg, uint8_t *value, uint8_t len);
uint8_t SPI_transfer(uint8_t pLoad);
bool isSending();

I cannot understand why I am getting a syntax error and any help will be greatly appreciated.
Thanks.