diff --git a/src/as/com/threerings/io/Streamer.as b/src/as/com/threerings/io/Streamer.as
index 7a71f357c..d912d01be 100644
--- a/src/as/com/threerings/io/Streamer.as
+++ b/src/as/com/threerings/io/Streamer.as
@@ -27,7 +27,6 @@ import flash.utils.Dictionary;
 import com.threerings.util.ByteEnum;
 import com.threerings.util.ClassUtil;
 import com.threerings.util.Enum;
-import com.threerings.util.env.Environment;
 
 import com.threerings.io.streamers.ArrayStreamer;
 import com.threerings.io.streamers.ByteStreamer;
@@ -78,11 +77,11 @@ public class Streamer
             // But: the code is smaller, so that wins
             var clazz :Class = ClassUtil.getClassByName(Translations.getFromServer(jname));
 
-            if (Environment.isAssignableAs(Enum, clazz)) {
-                streamer = Environment.isAssignableAs(ByteEnum, clazz) ?
+            if (ClassUtil.isAssignableAs(Enum, clazz)) {
+                streamer = ClassUtil.isAssignableAs(ByteEnum, clazz) ?
                     new ByteEnumStreamer(clazz, jname) : new EnumStreamer(clazz, jname);
 
-            } else if (Environment.isAssignableAs(Streamable, clazz)) {
+            } else if (ClassUtil.isAssignableAs(Streamable, clazz)) {
                 streamer = new Streamer(clazz, jname);
 
             } else {
diff --git a/src/as/com/threerings/io/streamers/ArrayStreamer.as b/src/as/com/threerings/io/streamers/ArrayStreamer.as
index 5e35ce4a4..63a23b08b 100644
--- a/src/as/com/threerings/io/streamers/ArrayStreamer.as
+++ b/src/as/com/threerings/io/streamers/ArrayStreamer.as
@@ -24,7 +24,6 @@ package com.threerings.io.streamers {
 import com.threerings.util.ClassUtil;
 import com.threerings.util.Enum;
 import com.threerings.util.Log;
-import com.threerings.util.env.Environment;
 
 import com.threerings.io.ArrayMask;
 import com.threerings.io.ObjectInputStream;
@@ -156,7 +155,7 @@ public class ArrayStreamer extends Streamer
         }
 
         // all enums are final, even if you forget to make your enum class final, you punk
-        if (Environment.isAssignableAs(Enum, type)) {
+        if (ClassUtil.isAssignableAs(Enum, type)) {
             return true;
         }