  We present the first measurements of the longitudinal double-spin asymmetry
$A_{LL}$ for dijets with at least one jet reconstructed within the
pseudorapidity range $0.8 < \eta < 1.8$. The dijets were measured in polarized
$pp$ collisions at a center-of-mass energy $\sqrt{s}$ = 200 GeV. Values for
$A_{LL}$ are determined for several distinct event topologies, defined by the
jet pseudorapidities, and span a range of parton momentum fraction $x$ down to
$x \sim$ 0.01. The measured asymmetries are found to be consistent with the
predictions of global analyses that incorporate the results of previous RHIC
measurements. They will provide new constraints on $\Delta g(x)$ in this poorly
constrained region when included in future global analyses.
