growfs reporting negative sectors beyond 2^31

While playing around with growfs I noticed that it prints the sector
numbers for the super-block backups on sectors beyond 2^31 as negative
numbers. I ran into this issue while trying to grow a 1TB filesystem to
a 1.5TB filesystem.

Example:
[snip]
2142948448, 2143324800, 2143701152, 2144077504, 2144453856, 2144830208,
2145206560, 2145582912, 2145959264,
2146335616, 2146711968, 2147088320, 2147464672, -2147126272,
-2146749920, -2146373568, -2145997216, -2145620864,
-2145244512, -2144868160, -2144491808, -2144115456, -2143739104,
-2143362752, -2142986400, -2142610048, -2142233696,
[snip]

Is this something to worry about as far as file system consistency goes,
or is it just a cosmetic problem with the printout?

Also, how safe is growfs to use. Are there any known problems?


/Daniel Eriksson