Forums Bug Reports sockread $+(&,%variable) - dynamic binary variable

sockread $+(&,%variable)
$bvar($+(&,%variable),0) = 0

sockread $+(&prefix,%variable)
$bvar($+(&prefix,%variable),0) = data length, its ok.

i used /sockread to dynamic $+(&,%variable), without any prefix, but $bvar($+(&,%variable),0) is $null

solve - using $eval(%variable,2) first:
sockread $+(&,$(,%variable))
$bvar($+(&,%variable),0) = data length, its ok.

but i think this is bug.