my $obj =  lockpan(); //interacts with a vb6 dll
my $enc_data = obj->encryptval($data); //returns binary val
$enc_data = '0x' . unpack('H*', $enc_data); //bin -> hex
#$enc_data is then written to a sql db as 7 bit ascii even parity

##</code><code>##

//enc_data is a hex formatted string generated by the the COM object my .net apps interact with. but in order for the .net app to decrypt the hex value returned by the same com object to perl the hex string must be transformed into the appropriate parity format by doing the following

enc_data = Regex.Replace(enc_data, "^0x", "");
enc_data = FromUnicodeByteArray( hex_to_bin(enc_data) );

//now enc_data contains a value that my .net app can send to the com object for decryption and get back the correct value

private static byte[] hex_to_bin ( string s ) 
		{ 
			int stringLength = s.Length; 
			if ( (stringLength & 0x1) != 0 ) 
			{ 
				Console.WriteLine("not even numbers");
			} 
			byte[] b = new byte[ stringLength / 2 ]; 

			for ( int i=0 ,j= 0; i< stringLength; i+= 2,j ++ ) 
			{ 
				int high= charToNibble( (s.Substring ( i,1 ).ToCharArray())[0]); 
				int low = charToNibble( (s.Substring(i+1,1).ToCharArray())[0] ); 
				b[ j ] = (byte ) ( ( high << 4 ) | low ); 
			} 
			return b; 
		} 

		/** 
		* convert a single char to corresponding nibble. 
		* 
		* @param c char to convert. must be 0-9 a-f A-F, no 
		* spaces, plus or minus signs. 
		* 
		* @return corresponding integer 
		*/ 
		private static int charToNibble ( char c ) 
		{ 
			if ( '0' <= c && c <= '9' ) 
			{ 
				return c - '0' ; 
			} 
			else if ( 'a' <= c && c <= 'f' ) 
			{ 
				return c - 'a' + 0xa ; 
			} 
			else if ( 'A' <= c && c <= 'F' ) 
			{ 
				return c - 'A' + 0xa ; 
			} 
			else 
			{ 
				Console.WriteLine( "Invalid hex character: " + c ) ; 
				return 0;
			} 
		} 
		
		private static string FromUnicodeByteArray(byte[] characters)
		{			
			string constructedString = Encoding.Default.GetString(characters);

			return (constructedString);
		}