diff --git a/indra/llmath/llvolume.cpp b/indra/llmath/llvolume.cpp
index 6005aa3f1d44be9b21ded1d2a0fbd8c7fe3544b7..be2a4ad1e8a4cdb323a539c6e57423b4676d0e4e 100644
--- a/indra/llmath/llvolume.cpp
+++ b/indra/llmath/llvolume.cpp
@@ -2630,7 +2630,7 @@ bool LLVolume::unpackVolumeFacesInternal(const LLSD& mdl)
                     continue;
                 }
 
-				const LLSD::Binary& weights = mdl_face["Weights"];
+				const LLSD::Binary& weights = mdl_face["Weights"].asBinary();
 
 				U32 idx = 0;