Don't use pnUtils for MD5 checksumming.

On the other hand, have we ever figured out exactly what this code is
supposed to do? Mark added it for something, but it's not really clear
what the purpose is.

Sources/Plasma/FeatureLib/pfPython/pyAgeInfoStruct.cpp

@@ -42,6 +42,7 @@ You can contact Cyan Worlds, Inc. by email legal@cyan.com
 #include "pyAgeInfoStruct.h"
 #include "hsStlUtils.h"
 #include "pnUtils/pnUtCrypt.h"
+#include "plEncryption/plChecksum.h"
 
 
 ///////////////////////////////////////////////////////////////////////////
@@ -129,9 +130,23 @@ void pyAgeInfoStruct::SetAgeInstanceGuid( const char * guid )
         // if it starts with an @ then do a meta kind of GUID
         std::string curInst = fAgeInfo.GetAgeInstanceName();
         std::string y = curInst + guid;
-       
+
         plUUID instanceGuid;
-        CryptDigest(kCryptMd5,  instanceGuid.fData , y.length(), y.c_str());
+        plMD5Checksum hash;
+        hash.Start();
+        hash.AddTo(y.length(), (uint8_t*)y.c_str());
+        hash.Finish();
+
+        const char* md5sum = hash.GetAsHexString();
+        plStringStream ss;
+        for (size_t i = 0; i < 16; i++) {
+            ss << md5sum[2*i];
+            ss << md5sum[(2*i)+1];
+
+            if (i == 3 || i == 5 || i == 7 || i == 9)
+                ss << '-';
+        }
+        instanceGuid.FromString(ss.GetString());
         fAgeInfo.SetAgeInstanceGuid(&instanceGuid);
     }
     else {