MD5("") = d41d8cd98f00b204e9800998ecf8427e  //ОК
MD5("md5") = 1bc29b36f623ba82aaf6724fd3b16718  //другое
MD5("md4") =  c93d3bf7a7c4afe94b64e30c2ce39f4f  //другое
Выдает MD5("md5") = MD5("md4") = другое

// of_MD5
/*FUNCTION Boolean CryptAcquireContextA (ref ulong hProv, &
      ref string pszContainer, &
      ref string pszProvider, ulong dwProvType, &
      ulong dwFlags) &
    LIBRARY "advapi32.dll"

 FUNCTION Boolean CryptReleaseContext (ulong hProv, ulong dwFlags) &
    LIBRARY "advapi32.dll"

 FUNCTION Boolean CryptCreateHash (ulong hProv, uint Algid, ulong hKey, &
      ulong dwFlags, ref ulong phHash) &
    LIBRARY "advapi32.dll"

 FUNCTION Boolean CryptHashData (ulong hHash,  ref string pbData, &
      ulong dwDataLen, ulong dwFlags) &
    LIBRARY "advapi32.dll"

 FUNCTION Boolean CryptDestroyHash (ulong hHash) &
    LIBRARY "advapi32.dll"

 FUNCTION Boolean CryptGetHashParam (ulong hHash, ulong dwParam, &
     ref blob pbData, &
     ref ulong pdwDataLen, ulong dwFlags) &
    LIBRARY "advapi32.dll"

 FUNCTION Ulong GetLastError () Library "kernel32.dll"
*/
CONSTANT ULONG CALG_MD5 =  32771 
CONSTANT ULONG PROV_RSA_FULL =  1 
CONSTANT ULONG HP_HASHVAL =  2 
CONSTANT ULONG CRYPT_VERIFYCONTEXT =  4026531840 
ulong 		MD5LEN =  16 
ulong 		cbHash
ulong 		hProv 	// provider handle
ulong 		hHash	 	// hash object handle
ulong 		err_number
String		s_result, s_null
Integer		i, l, r, b
Blob{ 16 }	bl_hash
Blob{ 1 } 	bl_byte

SetNull (s_null)
CHAR 	HexDigits[ 0  TO  15 ] = {'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'}

/*Get handle to the crypto provider*/
IF NOT CryptAcquireContextA( hProv, s_null, s_null, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT) THEN
  	err_number = GetLastError() 
  	return 'acquire context failed ' + String( err_number)
END IF

/*Create the hash object*/
IF NOT CryptCreateHash( hProv, CALG_MD5,  0 ,  0 , hHash) THEN
  	err_number = GetLastError()
  	CryptReleaseContext( hProv,  0 ) 
  	return 'create hash failed ' + String( err_number)
END IF

/*Add the input to the hash*/
/*IF NOT CryptHashData( hHash, as_text, Len( as_text), 0) THEN		//PB8-9*/
IF NOT CryptHashData( hHash, as_text, LenA( as_text),  0 ) THEN		/*PB10*/
	err_number = GetLastError()
  	CryptDestroyHash( hHash)
  	CryptReleaseContext( hProv,  0 ) 
  	return 'hashdata failed ' + String( err_number)
END IF

/*Get the hash value and convert it to readable characters*/
cbHash = MD5LEN
IF CryptGetHashParam( hHash, HP_HASHVAL, bl_hash, cbHash,  0 ) THEN
	  FOR i =  1  TO  16 
			bl_byte = BlobMid ( bl_hash, i,  1 )
		 /*b = Asc (String( bl_byte))	//PB8-9	*/	 
		 b = AscA( String( bl_byte, EncodingANSI!))	/*PB10*/
		 r = Mod( b,  16 ) 	/*right 4 bits*/
		 l = int( b /  16 )      	/* left 4 bits*/
		 s_result += HexDigits [l] + HexDigits [r]
	  NEXT
ELSE
  	err_number = GetLastError()
  	s_result = 'gethashparam failed ' + String( err_number)
END IF

/*clean up and return*/
CryptDestroyHash( hHash)
CryptReleaseContext( hProv,  0 )

return s_result

/*У меня выдает:*/
MD5("") = d41d8cd98f00b204e9800998ecf8427e  //совпадает
MD5("md5") = 8972340305B0D53BA4492AC367424F3E
MD5("md4") = 8972340305B0D53BA4492AC367424F3E

...
  // Add the input to the hash
  Blob bl_text
  bl_text = Blob(as_text, EncodingANSI!)
  IF NOT CryptHashData(hHash, bl_text, Len(bl_text),  0 ) THEN 
...

bl_text = Blob(as_text, EncodingANSI!)