Index: src/main/java/org/apache/james/imap/decode/base/FixedLengthInputStream.java
===================================================================
--- src/main/java/org/apache/james/imap/decode/base/FixedLengthInputStream.java	(revision 943140)
+++ src/main/java/org/apache/james/imap/decode/base/FixedLengthInputStream.java	(working copy)
@@ -60,16 +60,17 @@
             return -1;
         }
 
-        if (pos + b.length >= length) {
+        if (pos + len >= length) {
             int readLimit = (int) length - (int) pos;
             pos = length;
 
             return super.read(b, off, readLimit);
         }
 
-        pos += b.length;
 
-        return super.read(b, off, len);
+        int i =  super.read(b, off, len);
+        pos += i;
+        return i;
        
     }