Fix up certificate expiry detection

diff --git a/src/libtdeldap.cpp b/src/libtdeldap.cpp
index 940a91d..63ff769 100644
--- a/src/libtdeldap.cpp
+++ b/src/libtdeldap.cpp
@@ -4434,7 +4434,7 @@
 				KSSLCertificate* cert = KSSLCertificate::fromString(ssldata);
 				if (cert) {
 					bool expired = false;
-					if (TQDate::currentDate().daysTo(cert->getQDTNotAfter().date()) < 0) {
+					if (TQDateTime::currentDateTime(Qt::UTC) > cert->getQDTNotAfter()) {
 						expired = true;
 					}