Decode quoted-printable with bad line breaks

lib/mail/encodings/quoted_printable.rb

@@ -12,9 +12,10 @@ def self.can_encode?(str)
         EightBit.can_encode? str
       end
 
-      # Decode the string from Quoted-Printable
+      # Decode the string from Quoted-Printable. Cope with hard line breaks
+      # that were incorrectly encoded as hex instead of literal CRLF.
       def self.decode(str)
-        str.unpack("M*").first.to_lf
+        str.gsub(/(?:=0D=0A|=0D|=0A)\r\n/, "\r\n").unpack("M*").first.to_lf
       end
 
       def self.encode(str)

spec/mail/encodings/quoted_printable_spec.rb

@@ -31,5 +31,21 @@
     result = "\000\000\000\000"
     Mail::Encodings::QuotedPrintable.decode("=00=00=00=00").should eq result
   end
+
+  %w(=0D =0A =0D=0A).each do |linebreak|
+    expected = "first line wraps\n\nsecond paragraph"
+    it "should cope with inappropriate #{linebreak} line break encoding" do
+      body = "first line=\r\n wraps#{linebreak}\r\n#{linebreak}\r\nsecond paragraph=\r\n"
+      Mail::Encodings::QuotedPrintable.decode(body).should eq expected
+    end
+  end
+
+  [["\r", "=0D"], ["\n", "=0A"], ["\r\n", "=0D=0A"]].each do |crlf, linebreak|
+    expected = "first line wraps\n\nsecond paragraph"
+    it "should allow encoded #{linebreak} line breaks with soft line feeds" do
+      body = "first line=\r\n wraps#{linebreak}=\r\n#{linebreak}=\r\nsecond paragraph=\r\n"
+      Mail::Encodings::QuotedPrintable.decode(body).should eq expected
+    end
+  end
 
 end