diff --git a/build-tools/build.xml b/build-tools/build.xml
index 4ac2b4b017c..8d708cd316e 100644
--- a/build-tools/build.xml
+++ b/build-tools/build.xml
@@ -77,7 +77,7 @@
         <attribute name="file"           default=""/>
         <attribute name="srcdir"         default=""/>
         <attribute name="includeRuntime" default="true"/>
-        <attribute name="stdlib"         default="${kotlin-home}/lib/kotlin-runtime.jar"/>
+        <attribute name="stdlib"         default=""/>
 
         <sequential>
 
@@ -102,7 +102,7 @@
         <attribute name="srcdir"         default=""/>
         <attribute name="module"         default=""/>
         <attribute name="includeRuntime" default="true"/>
-        <attribute name="stdlib"         default="${kotlin-home}/lib/kotlin-runtime.jar"/>
+        <attribute name="stdlib"         default=""/>
         <sequential>
 
             <cleanup/>
diff --git a/build-tools/core/src/org/jetbrains/jet/buildtools/core/BytecodeCompiler.java b/build-tools/core/src/org/jetbrains/jet/buildtools/core/BytecodeCompiler.java
index 36825119b09..bb6c4c6d8e2 100644
--- a/build-tools/core/src/org/jetbrains/jet/buildtools/core/BytecodeCompiler.java
+++ b/build-tools/core/src/org/jetbrains/jet/buildtools/core/BytecodeCompiler.java
@@ -13,7 +13,7 @@ public class BytecodeCompiler {
 
     public BytecodeCompiler ( String stdlib ) {
         ENV = new CompileEnvironment();
-        if ( stdlib != null ) {
+        if (( stdlib != null ) && ( stdlib.trim().length() > 0 )) {
             ENV.setStdlib( stdlib );
         }
     }