Index: src/rendergl.m
==================================================================
--- src/rendergl.m
+++ src/rendergl.m
@@ -52,11 +52,12 @@
 	glCullFace(GL_FRONT);
 	glEnable(GL_CULL_FACE);
 
 	char *exts = (char *)glGetString(GL_EXTENSIONS);
 
-	if (strstr(exts, "GL_EXT_texture_env_combine"))
+	if (strstr(exts, "GL_EXT_texture_env_combine") ||
+	    strstr(exts, "GL_ARB_texture_env_combine"))
 		hasoverbright = true;
 	else
 		conoutf(@"WARNING: cannot use overbright lighting, using old "
 		    @"lighting model!");