Index: org/apache/pdfbox/pdmodel/font/PDSimpleFont.java
===================================================================
--- org/apache/pdfbox/pdmodel/font/PDSimpleFont.java	(revision 1638)
+++ org/apache/pdfbox/pdmodel/font/PDSimpleFont.java	(working copy)
@@ -109,6 +109,10 @@
             _awtFont = Font.decode(null); 
         }
 
+        if (_awtFont.getNumGlyphs() < 20) {
+           _awtFont = new Font(_awtFont.getName(), _awtFont.getStyle(), _awtFont.getSize());
+        }
+
         Graphics2D g2d = (Graphics2D)g;
         g2d.setRenderingHint( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON );
         writeFont(g2d, at, _awtFont, x, y, string);