i'm using jde 4.6... please take a look here: BlackBerry JDE 4.6.0 API Reference

it is clearly written:

Number of packets received by the radio, or -1 if this feature is not supported.

but now, when You've said this i've checked the 4.6.1 api and it is written:

Number of bytes received by the radio, or -1 if this feature is not supported.

so, i understand, You suggest to take what is written in 4.6.0 (also in 4.5.0) is a word mistake?
i'll try test it a little and check if that make sense.