diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java b/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java
index cf849e13bc3..9554d174b39 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java
@@ -303,7 +303,11 @@ public class NamespaceCodegen extends MemberCodegen {
 
         // dollar sign in the end is to prevent synthetic class from having "Test" or other parseable suffix
         // path hashCode to prevent same name / different path collision
-        return namespaceInternalName + "$src$" + name.substring(substringFrom, substringTo) + "$" + pathHashCode;
+        return namespaceInternalName + "$src$" + replaceSpecialSymbols(name.substring(substringFrom, substringTo)) + "$" + pathHashCode;
+    }
+
+    private static String replaceSpecialSymbols(@NotNull String str) {
+        return str.replace('.', '_');
     }
 
     @NotNull