Index: src/org/apache/pdfbox/io/RandomAccessBuffer.java
===================================================================
--- src/org/apache/pdfbox/io/RandomAccessBuffer.java	(revision 3)
+++ src/org/apache/pdfbox/io/RandomAccessBuffer.java	(working copy)
@@ -70,7 +70,7 @@
         {
             return -1;
         }
-        int result = buffer[(int)pointer];
+        int result = buffer[(int)pointer] & 0xff;
         pointer++;
         return result;
     }