linking problem in DPAPI

["bubble" <bubble@riskm.com.tw>]

dear all:
I got a problem again :)

I am write a little security binding for my application.
and I got a error message.
....app.o(.text+0x3914):app.adb: undefined reference to 
`CryptProtectData@28'

what's the problem?
give me a hint. thanks
my compiler is [gnat gpl 2005] and my OS is windows xp.



with Win32;
With Win32.Windef;

package app.Security Is


   type Data_Blob is record
      Cbdata : Win32.DWORD;
      Pbdata : Win32.PBYTE;
   end record;
   Pragma Convention(c_pass_by_copy,Data_Blob);

   Type Access_Data_Blob Is Access All Data_Blob;

   Type CRYPTPROTECT_PROMPTSTRUCT Is Record
      Cbsize:Win32.Dword;
      DwPromptFlags:Win32.DWord;
      Hwandapp:Win32.Windef.Hwnd;
      SzPrompt:Win32.Lpcwstr;
   End Record;
   Pragma Convention(c_pass_by_copy,CRYPTPROTECT_PROMPTSTRUCT);
   Type Access_CRYPTPROTECT_PROMPTSTRUCT Is Access All 
CRYPTPROTECT_PROMPTSTRUCT;


   Function CryptProtectData(Pdatain:Access_Data_Blob;
                             SzDataDescr:Win32.Lpcwstr;
                             POptionalEntropy:Access_Data_Blob;
                             PvReserved:Win32.Pvoid;
                             pPromptStruct 
:Access_CRYPTPROTECT_PROMPTSTRUCT;
                             dwFlags :Win32.Dword;
                             Pdataout:Access_Data_Blob) Return Win32.Bool;
   Pragma Import(Stdcall,CryptProtectData,"CryptProtectData");
   Pragma Linker_Options("-lcrypt32");




end app.Security;