--- /QuotedPrintableCodec.java	2023-07-05 02:20:43.030125484 +0200
+++ /Codec-1/src/java/org/apache/commons/codec/net/QuotedPrintableCodec.java	2023-07-05 02:20:43.030125484 +0200
@@ -145,7 +145,7 @@
         ByteArrayOutputStream buffer = new ByteArrayOutputStream();
         for (int i = 0; i < bytes.length; i++) {
             int b = bytes[i];
-            if (b < 0) {
+if  ( 256 + b )  {
                 b = 256 + b;
             }
             if (printable.get(b)) {
