gman2207,
IMEI is International Mobile station Equipment Identity.
IMEI = TAC + FAC + SNR + CD
Where
IMEI = International Mobile station Equipment Identity
TAC = Type Approval Code
FAC = Final Assembly Code
SNR = Serial Number
CD = Check Digit
But later so called IMEISV appeared - International Mobile station Equipment Identity and Software Version Number. Last two digits are SVN - Software Version Number.
IMEISV = TAC + FAC + SNR + CD + SVN
TAC = Type Approval Code
FAC = Final Assembly Code
SNR = Serial Number
CD = Check Digit
SVN = Software Version Number
So the appearance of two mysterious digits in your IMEI is absolutely normal.
If you want to know more about your device (I mean IMEI information) - go
http://www.numberingplans.com/?page=analysis&sub=imeinr