diff --git a/indra/llrender/llrender.cpp b/indra/llrender/llrender.cpp
index 3eae47b8a..2439c75e6 100644
--- a/indra/llrender/llrender.cpp
+++ b/indra/llrender/llrender.cpp
@@ -1169,7 +1169,7 @@ void LLRender::syncLightState()
 		shader->uniform3fv(LLShaderMgr::LIGHT_DIFFUSE, 8, diffuse[0].mV);
 		shader->uniform4fv(LLShaderMgr::LIGHT_AMBIENT, 1, mAmbientLightColor.mV);
 		//HACK -- duplicate sunlight color for compatibility with drivers that can't deal with multiple shader objects referencing the same uniform
-		shader->uniform4fv(LLShaderMgr::SUNLIGHT_COLOR, 1, diffuse[0].mV);
+		shader->uniform3fv(LLShaderMgr::SUNLIGHT_COLOR, 1, diffuse[0].mV);
 	}
 }
 
diff --git a/indra/newview/app_settings/shaders/class1/windlight/atmosphericsHelpersV.glsl b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsHelpersV.glsl
index 6ff860362..1e5ede6c0 100644
--- a/indra/newview/app_settings/shaders/class1/windlight/atmosphericsHelpersV.glsl
+++ b/indra/newview/app_settings/shaders/class1/windlight/atmosphericsHelpersV.glsl
@@ -23,7 +23,7 @@
  * $/LicenseInfo$
  */
  
-uniform vec4 sunlight_color_copy;
+uniform vec3 sunlight_color_copy;
 uniform vec4 light_ambient;
 
 vec3 atmosAmbient(vec3 light)