Re: [Solution] The lost key (Chris, do not read! :-)

Marcel Logen in sci.crypt:

[...]

 This data has an odd number of hex digits, so prepend a "0";
 then you can use the Linux tool "xxd" for transformation to
 readable text:

If you want to use this method for 'encrypting' binary
data, I would recommend prefixing the data with 0xFF or
0x80 before encryption - and removing it again after
decryption.

| user15@o15:/tmp$ { echo -n 'ibase=16;' && echo '000102030405060708090A0B0C0D0E0F' ; } | BC_LINE_LENGTH=0 bc
| 5233100606242806050955395731361295

| user15@o15:/tmp$ { echo 'obase=16' && echo '5233100606242806050955395731361295' ; } | BC_LINE_LENGTH=0 bc
| 102030405060708090A0B0C0D0E0F

With 0xFF prepended:

| user15@o15:/tmp$ { echo -n 'ibase=16;' && echo 'FF000102030405060708090A0B0C0D0E0F' ; } | BC_LINE_LENGTH=0 bc
| 86772008797939914425966575850496625282575

| user15@o15:/tmp$ { echo 'obase=16' && echo '86772008797939914425966575850496625282575' ; } | BC_LINE_LENGTH=0 bc
| FF000102030405060708090A0B0C0D0E0F

Marcel                                                       (Lines: 33)
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