diff --git a/classpath/java-lang.cpp b/classpath/java-lang.cpp
index 3cd963eee1..6f680f12e7 100644
--- a/classpath/java-lang.cpp
+++ b/classpath/java-lang.cpp
@@ -71,8 +71,11 @@ Java_java_lang_System_doMapLibraryName(JNIEnv* e, jclass, jstring name)
 }
 
 extern "C" JNIEXPORT jint JNICALL
-Java_java_lang_Double_fillBufferWithDouble(JNIEnv *e, jclass me, jdouble val,
+Java_java_lang_Double_fillBufferWithDouble(JNIEnv *e, jclass, jdouble val,
 					   jbyteArray buffer, jint bufferSize) {
-  if (e or me or val or buffer or bufferSize) return 0;
-  return 0;
+  jboolean isCopy;
+  jbyte* buf = e->GetByteArrayElements(buffer, &isCopy);
+  jint count = snprintf(reinterpret_cast<char*>(buf), bufferSize, "%g", val);
+  e->ReleaseByteArrayElements(buffer, buf, 0);
+  return count;
 }
diff --git a/classpath/java/lang/Float.java b/classpath/java/lang/Float.java
index b563a69bf4..88274aa4e9 100644
--- a/classpath/java/lang/Float.java
+++ b/classpath/java/lang/Float.java
@@ -26,7 +26,7 @@ public final class Float extends Number {
   }
 
   public static String toString(float v) {
-    return "Float.toString: todo";
+    return Double.toString(v);
   }
 
   public byte byteValue() {