diff --git a/src/kits/network/libnetapi/NetworkCookie.cpp b/src/kits/network/libnetapi/NetworkCookie.cpp
index 253e624f4c..4b5c4fb87c 100644
--- a/src/kits/network/libnetapi/NetworkCookie.cpp
+++ b/src/kits/network/libnetapi/NetworkCookie.cpp
@@ -232,7 +232,7 @@ BNetworkCookie::SetExpirationDate(time_t expireDate)
 BNetworkCookie&
 BNetworkCookie::SetExpirationDate(BDateTime& expireDate)
 {
-	if (expireDate.Time_t() <= 0) {
+	if (!expireDate.IsValid()) {
 		fExpiration.SetTime_t(0);
 		fSessionCookie = true;
 		fExpirationStringValid = false;