Fix bug 128513 by properly initializing the creation time of a signature. In case of clear signed messages we can't parse the date, so don't show it.

BUG:128513

svn path=/branches/KDE/3.5/kdepim/; revision=547690

partmetadata.h

@@ -35,7 +35,12 @@ namespace KMail {
         isEncrypted( false ),
         isDecryptable( false ),
         technicalProblem( false ),
-        isEncapsulatedRfc822Message( false ) {}
+        isEncapsulatedRfc822Message( false )
+    {
+      creationTime.tm_year = 0;
+      creationTime.tm_mon  = 1;
+      creationTime.tm_mday = 1;
+    }
     bool isSigned;
     bool isGoodSignature;
     CryptPlugWrapper::SigStatusFlags sigStatusFlags;