Error while writing/reading I2C EEPROM

[40inD]

When i write the int number into eeprom and then read it, it is not the same. For ex. when i write 0 - i read 0, when i write 1, i read 127, when i write 2 or 3 i read 128, when i write 4 - i read 129... when i write 25 - i read 134. What is wrong?
i use standart 2464.c driver for 24LC64 and my functions are:

#define ADR_TMODE 5
int tmode

write_ext_eeprom(ADR_TMODE, tmode);

tmode=read_ext_eeprom(ADR_TMODE);