diff --git a/libjava/ChangeLog b/libjava/ChangeLog
index 81cb27fe4a5..27569940330 100644
--- a/libjava/ChangeLog
+++ b/libjava/ChangeLog
@@ -4,6 +4,11 @@
 	property is not set. Don't call decode with null argument.
 	* java/lang/Long.java (getLong): Likewise.
 
+	* java/io/CharArrayReader.java (CharArrayReader): Throw 
+	IllegalArgumentException if constructor arguments are illegal.
+	(ready): Return false if no more characters can be read.
+	* java/io/ByteArrayInputStream.java (ByteArrayInputStream): Likewise.
+
 2001-02-17  Mark Wielaard <mark@klomp.org>
 
 	* java/util/TimerTask.java: New version from Classpath.
diff --git a/libjava/java/io/ByteArrayInputStream.java b/libjava/java/io/ByteArrayInputStream.java
index 30ba8d7f9da..0d9339363c1 100644
--- a/libjava/java/io/ByteArrayInputStream.java
+++ b/libjava/java/io/ByteArrayInputStream.java
@@ -40,6 +40,9 @@ public class ByteArrayInputStream extends InputStream
 
   public ByteArrayInputStream(byte[] buffer, int offset, int length)
   {
+    if (offset < 0  || length < 0 || offset > buffer.length)
+      throw new IllegalArgumentException();
+
     buf = buffer;
 
     count = offset + length;
@@ -47,10 +50,6 @@ public class ByteArrayInputStream extends InputStream
       count = buf.length;
 
     pos = offset;
-    // TBD: What should we do if pos is neg. or > count?  E.g. throw exc. or:
-    // if (pos < 0 || pos > count)
-    //   pos = 0;
-
     mark = pos;
   }
 
diff --git a/libjava/java/io/CharArrayReader.java b/libjava/java/io/CharArrayReader.java
index 0a77998445f..d67c7c79f5c 100644
--- a/libjava/java/io/CharArrayReader.java
+++ b/libjava/java/io/CharArrayReader.java
@@ -41,17 +41,16 @@ public class CharArrayReader extends Reader
   public CharArrayReader(char[] buffer, int offset, int length)
   {
     super();
+    if (offset < 0  || length < 0 || offset > buffer.length)
+      throw new IllegalArgumentException();
+    
     buf = buffer;
 
     count = offset + length;
     if (count > buf.length)
       count = buf.length;
-
+    
     pos = offset;
-    // TBD: What should we do if pos is neg. or > count?  E.g. throw exc. or:
-    // if (pos < 0 || pos > count)
-    //   pos = 0;
-
     markedPos = pos;
   }
 
@@ -116,12 +115,17 @@ public class CharArrayReader extends Reader
     }
   }
 
+  /** Return true if more characters are available to be read. 
+    *
+    * @specnote The JDK 1.3 API docs are wrong here. This method will
+    *           return false if there are no more characters available.
+    */
   public boolean ready() throws IOException
   {
     if (buf == null)
       throw new IOException("Stream closed");
 
-    return true;
+    return (pos < count);
   }
 
   public void reset() throws IOException